ComboBox AutoComplete на SubString

В одном из моих приложений WinForms у меня есть окно с ComboBox для того, чтобы пользователь мог выбрать клиента.

Клиенты в этом списке находятся в таком формате: "CustomerID - CustomerName", например "004540 - NorthWind Traders"

У родного WinBorms combobox есть встроенная функция автозаполнения, и она работает хорошо: проблема в том, что она работает только путем сопоставления с началом строки каждого элемента списка combobox, а не из любой точки (подстрока).

То, что я хотел бы, чтобы мои пользователи могли делать это, - это любой тип CustomerID или CustomerName, поскольку старшие пользователи знакомы с большинством идентификаторов клиентов, в то время как новым рекрутам будет полезно иметь возможность вводить имя CustomerName и получать автозаполнение в любом случае, Это означает, что я действительно хочу найти наилучшее соответствие из списка, где введенный текст является подстрокой элемента ComboBox.

Решение, часто предлагаемое для такого рода сценариев, заключается в создании скрытого списка, которое появляется только тогда, когда пользователь вводит его, но я не доволен тем, что он похож на быстрый хак и не может быть легко повторно использован и могут выглядеть и вести себя непоследовательно по сравнению со стандартным контроллером ComboBox.

Я попытался реализовать это самостоятельно, используя свойство DroppedDown, чтобы создать список и использовать SelectedIndex для установки элемента, но содержимое текстового поля combobox reset, когда я это делаю, в то время как мне только хотелось бы, чтобы "наилучший совпадающий элемент", который будет выделен из списков ComboBox (мне нужно "Предложить", а не "Добавить", Append-режим не может быть действительно использован с подстрокой в ​​любом случае).

Я думаю, что должен быть лучший способ? Если кто-то знает о пользовательском/стороннем контроле, делающем это, я не против покупать его.

Спасибо.

PS: Я программирую на С# для WinForms, с .Net Framework 3.5.

ОТВЕТЫ

Ответ 1

Ну, у меня есть код для вас, чтобы попробовать. Это не поле со списком, а текстовое поле с автозаполнением и изменениями, которые выполняются в соответствии с вашими требованиями.

Скопируйте код в новую форму. Затем, прежде чем делать что-либо еще, сохраните и постройте. Затем перейдите к конструктору форм и перетащите новый ClsCustomAutoCompleteTextbox на свою форму.

Тогда вы должны быть в состоянии запустить его. Я понимаю, что вы хотите С# (по крайней мере, теперь я это понимаю). Попробуйте это в VB и посмотрите, хотите ли вы, и я могу преобразовать это в С#.

Public Class Form1
  Dim MasterList As New List(Of String)


  Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    Dim L As New List(Of String)

    L.Add("123123 - Bob")
    L.Add("534543 - Sally")
    L.Add("123123 - George")
    L.Add("34213 - Happy")

    MasterList = L

    Me.ClsCustomAutoCompleteTextbox1.AutoCompleteList = L
  End Sub

  Private Sub ClsCustomAutoCompleteTextbox1_BeforeDisplayingAutoComplete(ByVal sender As Object, ByVal e As clsCustomAutoCompleteTextbox.clsAutoCompleteEventArgs) Handles ClsCustomAutoCompleteTextbox1.BeforeDisplayingAutoComplete

    Dim Name As String = Me.ClsCustomAutoCompleteTextbox1.Text.ToLower

    Dim Display As New List(Of String)

    For Each Str As String In MasterList
      If Str.ToLower.IndexOf(Name) > -1 Then
        Display.Add(Str)
      End If
    Next

    e.AutoCompleteList = Display
    e.SelectedIndex = 0
  End Sub
End Class


#Region "clsCustomAutoCompleteTextbox"
Public Class clsCustomAutoCompleteTextbox
  Inherits TextBox
  Event BeforeDisplayingAutoComplete(ByVal sender As Object, ByVal e As clsAutoCompleteEventArgs)
  Event ItemSelected(ByVal sender As Object, ByVal e As clsItemSelectedEventArgs)


  Public test As New List(Of String)
  Public Tabs As Integer = 0


  Private Function GetLastFunction(Optional ByVal Deep As Integer = 1) As System.Reflection.MethodInfo
    Dim ST As New StackTrace
    Dim Frame As StackFrame = ST.GetFrame(Deep)

    Return Frame.GetMethod()
  End Function

  Private Sub TempLogStart()
    'Dim Meth As System.Reflection.MethodInfo = GetLastFunction(3)

    'test.Add(Now & " - " & New String(" ", Tabs * 2) & "Started " & Meth.Module.Name & "." & Meth.Name)

    'Tabs += 1
  End Sub

  Private Sub TempLogStop()
    '  Dim Meth As System.Reflection.MethodInfo = GetLastFunction(3)

    '  Tabs -= 1

    '  test.Add(Now & " - " & New String(" ", Tabs * 2) & "Stopped " & Meth.Module.Name & "." & Meth.Name)
  End Sub

  Public Enum SelectOptions
    OnEnterPress = 1
    OnSingleClick = 2
    OnDoubleClick = 4
    OnTabPress = 8
    OnRightArrow = 16
    OnEnterSingleClick = 3
    OnEnterSingleDoubleClicks = 7
    OnEnterDoubleClick = 5
    OnEnterTab = 9
    'OnItemChange = 32
  End Enum

  Private mSelStart As Integer
  Private mSelLength As Integer

  Private myAutoCompleteList As New List(Of String)
  Private WithEvents myLbox As New ListBox
  Private WithEvents myForm As New Form
  Private WithEvents myParentForm As Form

  Private DontHide As Boolean = False
  Private SuspendFocus As Boolean = False

  Dim Args As clsAutoCompleteEventArgs

  WithEvents HideTimer As New Timer()
  WithEvents FocusTimer As New Timer()

  Private myShowAutoCompleteOnFocus As Boolean
  Private myAutoCompleteFormBorder As System.Windows.Forms.FormBorderStyle = FormBorderStyle.None
  Private myOnEnterSelect As Boolean
  Private mySelectionMethods As SelectOptions = (SelectOptions.OnDoubleClick Or SelectOptions.OnEnterPress)
  Private mySelectTextAfterItemSelect As Boolean = True


  Public Property SelectTextAfterItemSelect() As Boolean
    Get
      Return mySelectTextAfterItemSelect
    End Get
    Set(ByVal value As Boolean)
      mySelectTextAfterItemSelect = value
    End Set
  End Property

  <System.ComponentModel.Browsable(False)> _
  Public Property SelectionMethods() As SelectOptions
    Get
      Return mySelectionMethods
    End Get
    Set(ByVal value As SelectOptions)
      mySelectionMethods = value
    End Set
  End Property

  Public Property OnEnterSelect() As Boolean
    Get
      Return myOnEnterSelect
    End Get
    Set(ByVal value As Boolean)
      myOnEnterSelect = value
    End Set
  End Property

  Public Property AutoCompleteFormBorder() As System.Windows.Forms.FormBorderStyle
    Get
      Return myAutoCompleteFormBorder
    End Get
    Set(ByVal value As System.Windows.Forms.FormBorderStyle)
      myAutoCompleteFormBorder = value
    End Set
  End Property

  Public Property ShowAutoCompleteOnFocus() As Boolean
    Get
      Return myShowAutoCompleteOnFocus
    End Get
    Set(ByVal value As Boolean)
      myShowAutoCompleteOnFocus = value
    End Set
  End Property

  Public ReadOnly Property Lbox() As ListBox
    Get
      Return myLbox
    End Get
  End Property

  Public Property AutoCompleteList() As List(Of String)
    Get
      Return myAutoCompleteList
    End Get
    Set(ByVal value As List(Of String))
      myAutoCompleteList = value
    End Set
  End Property

  Private Sub TryHideFormWindowsDeactivated()

  End Sub

  Private Declare Auto Function GetForegroundWindow Lib "user32.dll" () As IntPtr
  Private Declare Auto Function GetWindowThreadProcessId Lib "user32.dll" (ByVal hWnd As IntPtr, ByRef ProcessID As Integer) As Integer

  Private Function IsCurProcess(ByVal P As Process) As Boolean
    Dim Ptr As IntPtr = P.MainWindowHandle


  End Function

  Private Function AppHasFocus(Optional ByVal ExeNameWithoutExtension As String = "") As Boolean
    Dim Out As Boolean = False
    Dim PID As Integer = 0

    TempLogStart()

    If ExeNameWithoutExtension = "" Then
      ExeNameWithoutExtension = Process.GetCurrentProcess.ProcessName
    End If
    Dim activeHandle As IntPtr = GetForegroundWindow()
    Call GetWindowThreadProcessId(activeHandle, PID)
    If PID > 0 Then
      'For Each p As Process In Process.GetProcessesByName(ExeNameWithoutExtension)
      If PID = Process.GetCurrentProcess.Id Then
        Out = True
        'Exit For
      End If
      ' Next
    End If

    TempLogStop()

    Return Out
  End Function

  Private Sub SaveSelects()
    Me.mSelStart = Me.SelectionStart
    Me.mSelLength = Me.SelectionLength
  End Sub

  Private Sub LoadSelects()
    Me.SelectionStart = Me.mSelStart
    Me.SelectionLength = Me.mSelLength
  End Sub

  Private Sub ShowAutoComplete()
    TempLogStart()

    Args = New clsAutoCompleteEventArgs()

    With Args
      .Cancel = False
      .AutoCompleteList = Me.myAutoCompleteList

      If myLbox.SelectedIndex = -1 Then
        .SelectedIndex = 0
      Else
        .SelectedIndex = myLbox.SelectedIndex
      End If
    End With

    RaiseEvent BeforeDisplayingAutoComplete(Me, Args)

    Me.myAutoCompleteList = Args.AutoCompleteList

    'If Me.myAutoCompleteList IsNot Nothing AndAlso Me.myAutoCompleteList.Count - 1 < Args.SelectedIndex Then
    '  Args.SelectedIndex = Me.myAutoCompleteList.Count - 1
    'End If

    If Not Args.Cancel AndAlso Args.AutoCompleteList IsNot Nothing AndAlso Args.AutoCompleteList.Count > 0 Then
      Call DoShowAuto()
    Else
      Call DoHideAuto()
    End If
    TempLogStop()
  End Sub

  Private Sub DoShowAuto()
    Call SaveSelects()

    TempLogStart()
    Static First As Boolean = True
    myLbox.BeginUpdate()
    Try
      myLbox.Items.Clear()
      myLbox.Items.AddRange(Me.myAutoCompleteList.ToArray)

      Call Me.MoveLBox(Args.SelectedIndex)
    Catch ex As Exception
    End Try
    myLbox.EndUpdate()


    myParentForm = GetParentForm(Me)
    If myParentForm IsNot Nothing Then
      myLbox.Name = "mmmlbox" & Now.Millisecond
      If myForm.Visible = False Then
        myForm.Font = Me.Font
        myLbox.Font = Me.Font

        myLbox.Visible = True
        myForm.Visible = False

        myForm.ControlBox = False

        myForm.Text = ""

        If First Then
          myForm.Width = Me.Width
          myForm.Height = 200
        End If

        First = False

        If Not myForm.Controls.Contains(myLbox) Then myForm.Controls.Add(myLbox)
        myForm.FormBorderStyle = FormBorderStyle.None
        myForm.ShowInTaskbar = False

        With myLbox
          .Dock = DockStyle.Fill
          .SelectionMode = SelectionMode.One
        End With

        'Frm.Controls.Add(myLbox)

        DontHide = True

        SuspendFocus = True


        myForm.TopMost = True
        myForm.FormBorderStyle = Me.myAutoCompleteFormBorder

        myForm.BringToFront()
        Call MoveDrop()
        myForm.Visible = True
        myForm.Show()
        Call MoveDrop()

        HideTimer.Interval = 10

        Me.Focus()

        SuspendFocus = False

        HideTimer.Enabled = True

        DontHide = False

        Call LoadSelects()
      End If
    End If
    TempLogStop()

  End Sub

  Sub MoveDrop()

    TempLogStart()
    Dim Pnt As Point = New Point(Me.Left, Me.Top + Me.Height + 2)
    Dim ScreenPnt As Point = Me.PointToScreen(New Point(-2, Me.Height))

    'Dim FrmPnt As Point = Frm.PointToClient(ScreenPnt)
    If myForm IsNot Nothing Then
      myForm.Location = ScreenPnt

      'myForm.BringToFront()


      'myForm.Focus()
      'myLbox.Focus()

      'Me.Focus()
    End If
    TempLogStop()
  End Sub

  Sub DoHide(ByVal sender As Object, ByVal e As EventArgs)

    TempLogStart()
    Call HideAuto()
    TempLogStop()
  End Sub

  Private Sub DFocus(Optional ByVal Delay As Integer = 10)

    TempLogStart()
    FocusTimer.Interval = Delay
    FocusTimer.Start()
    TempLogStop()
  End Sub

  Private Sub DoHideAuto()

    TempLogStart()
    myForm.Hide()

    HideTimer.Enabled = False
    FocusTimer.Enabled = False
    TempLogStop()
  End Sub

  Private Sub HideAuto()

    TempLogStart()
    If myForm.Visible AndAlso HasLostFocus() Then
      Call DoHideAuto()
    End If
    TempLogStop()
  End Sub

  Private Function HasLostFocus() As Boolean

    TempLogStart()
    Dim Out As Boolean

    If Me.myForm Is Nothing OrElse myForm.ActiveControl IsNot Me.myLbox Then
      Out = True
    End If

    If Me.myParentForm Is Nothing OrElse Me.myParentForm.ActiveControl IsNot Me Then
      Out = True
    End If

    TempLogStop()
    Return Out
  End Function

  Private Function GetParentForm(ByVal InCon As Control) As Form

    TempLogStart()
    Dim TopCon As Control = FindTopParent(InCon)
    Dim Out As Form = Nothing

    If TypeOf TopCon Is Form Then
      Out = CType(TopCon, Form)
    End If

    TempLogStop()
    Return Out
  End Function

  Private Function FindTopParent(ByVal InCon As Control) As Control

    TempLogStart()
    Dim Out As Control

    If InCon.Parent Is Nothing Then
      Out = InCon
    Else
      Out = FindTopParent(InCon.Parent)
    End If

    TempLogStop()
    Return Out
  End Function

  Public Class clsAutoCompleteEventArgs
    Inherits EventArgs

    Private myAutoCompleteList As List(Of String)
    Private myCancel As Boolean

    Private mySelectedIndex As Integer

    Public Property SelectedIndex() As Integer
      Get
        Return mySelectedIndex
      End Get
      Set(ByVal value As Integer)
        mySelectedIndex = value
      End Set
    End Property

    Public Property Cancel() As Boolean
      Get
        Return myCancel
      End Get
      Set(ByVal value As Boolean)
        myCancel = value
      End Set
    End Property

    Public Property AutoCompleteList() As List(Of String)
      Get
        Return myAutoCompleteList
      End Get
      Set(ByVal value As List(Of String))
        myAutoCompleteList = value
      End Set
    End Property
  End Class

  Protected Overrides Sub OnKeyUp(ByVal e As System.Windows.Forms.KeyEventArgs)

    TempLogStart()
    TempLogStop()
    MyBase.OnKeyUp(e)

    Call ShowOnChar(Chr(e.KeyValue))
  End Sub

  Private Sub ShowOnChar(ByVal C As String)

    TempLogStart()
    TempLogStop()
    If IsPrintChar(C) Then
      Call Me.ShowAutoComplete()
    End If
  End Sub

  Private Function IsPrintChar(ByVal C As Integer) As Boolean

    TempLogStart()
    TempLogStop()
    Return IsPrintChar(Chr(C))
  End Function

  Private Function IsPrintChar(ByVal C As Byte) As Boolean

    TempLogStart()
    TempLogStop()
    Return IsPrintChar(Chr(C))
  End Function

  Private Function IsPrintChar(ByVal C As Char) As Boolean

    TempLogStart()
    TempLogStop()
    Return IsPrintChar(C.ToString)
  End Function

  Private Function IsPrintChar(ByVal C As String) As Boolean

    TempLogStart()
    If System.Text.RegularExpressions.Regex.IsMatch(C, "[^\t\n\r\f\v]") Then
      Return True
    Else
      Return False
    End If
    TempLogStop()
  End Function

  Private Sub clsCustomAutoCompleteTextbox_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.GotFocus

    TempLogStart()
    If Not Me.SuspendFocus AndAlso Me.myShowAutoCompleteOnFocus AndAlso Me.myForm.Visible = False Then
      Call Me.ShowAutoComplete()
    End If
    TempLogStop()
  End Sub

  Private Sub clsCustomAutoCompleteTextbox_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles Me.KeyDown

    TempLogStart()
    If Not SelectItem(e.KeyCode) Then
      If e.KeyCode = Keys.Up Then
        If myLbox.SelectedIndex > 0 Then
          Call MoveLBox(myLbox.SelectedIndex - 1)
        End If
      ElseIf e.KeyCode = Keys.Down Then
        Call MoveLBox(myLbox.SelectedIndex + 1)
      End If
    End If
    TempLogStop()
  End Sub

  Shadows Sub SelectAll()

  End Sub

  Private Sub MoveLBox(ByVal Index As Integer)

    TempLogStart()
    Try
      If Index > myLbox.Items.Count - 1 Then
        Index = myLbox.Items.Count - 1
      End If

      myLbox.SelectedIndex = Index
    Catch ex As Exception

    End Try
    TempLogStop()
  End Sub

  Private Sub clsCustomAutoCompleteTextbox_Leave(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Leave

    TempLogStart()
    Call DoHide(sender, e)
    TempLogStop()
  End Sub

  Private Sub clsCustomAutoCompleteTextbox_LostFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.LostFocus

    TempLogStart()
    Call DoHide(sender, e)
    TempLogStop()
  End Sub

  Private Sub clsCustomAutoCompleteTextbox_Move(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Move

    TempLogStart()
    Call MoveDrop()
    TempLogStop()
  End Sub

  Private Sub clsCustomAutoCompleteTextbox_ParentChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.ParentChanged

    TempLogStart()
    myParentForm = GetParentForm(Me)
    TempLogStop()
  End Sub

  Private Sub HideTimer_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles HideTimer.Tick

    TempLogStart()
    Call MoveDrop()
    Call DoHide(sender, e)

    Static Cnt As Integer = 0

    Cnt += 1

    If Cnt > 300 Then
      If Not AppHasFocus() Then
        Call DoHideAuto()
      End If

      Cnt = 0
    End If
    TempLogStop()
  End Sub

  Public Overrides Property SelectedText() As String
    Get
      Return MyBase.SelectedText
    End Get
    Set(ByVal value As String)
      MyBase.SelectedText = value
    End Set
  End Property

  Public Overrides Property SelectionLength() As Integer
    Get
      Return MyBase.SelectionLength
    End Get
    Set(ByVal value As Integer)
      MyBase.SelectionLength = value
    End Set
  End Property

  Private Sub myLbox_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles myLbox.Click


  End Sub

  Private Sub myLbox_DoubleClick(ByVal sender As Object, ByVal e As System.EventArgs) Handles myLbox.DoubleClick

  End Sub

  Private Function SelectItem(Optional ByVal Key As Keys = Keys.None, _
                         Optional ByVal SingleClick As Boolean = False, _
                         Optional ByVal DoubleClick As Boolean = False) As Boolean


    TempLogStart()
    Dim DoSelect As Boolean = True
    Dim Meth As SelectOptions
    Static LastItem As Integer = -1
    Select Case True
      Case Me.mySelectionMethods And SelectOptions.OnEnterPress AndAlso Key = Keys.Enter
        Meth = SelectOptions.OnEnterPress
      Case Me.mySelectionMethods And SelectOptions.OnRightArrow AndAlso Key = Keys.Right
        Meth = SelectOptions.OnRightArrow
      Case Me.mySelectionMethods And SelectOptions.OnTabPress AndAlso Key = Keys.Tab
        Meth = SelectOptions.OnTabPress
      Case Me.mySelectionMethods And SelectOptions.OnSingleClick AndAlso SingleClick
        Meth = SelectOptions.OnSingleClick
      Case Me.mySelectionMethods And SelectOptions.OnDoubleClick AndAlso DoubleClick
        Meth = SelectOptions.OnDoubleClick
        'Case Me.mySelectionMethods And SelectOptions.OnItemChange AndAlso (LastItem <> myLbox.SelectedIndex)
      Case Else
        DoSelect = False
    End Select
    LastItem = myLbox.SelectedIndex
    If DoSelect Then
      Call DoSelectItem(Meth)
    End If
    TempLogStop()

    Return DoSelect
  End Function

  Private Sub DoSelectItem(ByVal Method As SelectOptions)

    TempLogStart()
    If Me.myLbox.Items.Count > 0 AndAlso Me.myLbox.SelectedIndex > -1 Then
      Dim Value As String = Me.myLbox.SelectedItem.ToString

      Dim Orig As String = Me.Text

      Me.Text = Value

      If mySelectTextAfterItemSelect Then
        Try
          Me.SelectionStart = Orig.Length
          Me.SelectionLength = Value.Length - Orig.Length
        Catch ex As Exception
        End Try
      Else
        'Me.SelectionStart = Me.Text.Length
        'Me.SelectionLength = 0
      End If

      RaiseEvent ItemSelected(Me, New clsItemSelectedEventArgs(Me.myLbox.SelectedIndex, Method, Value))

      Call Me.DoHideAuto()
    End If
    TempLogStop()
  End Sub

  Public Class clsItemSelectedEventArgs
    Private myIndex As Integer
    Private myMethod As SelectOptions
    Private myItemText As String

    Public Property ItemText() As Boolean
      Get
        Return myItemText
      End Get
      Set(ByVal value As Boolean)
        myItemText = value
      End Set
    End Property

    Public Property Method() As SelectOptions
      Get
        Return myMethod
      End Get
      Set(ByVal value As SelectOptions)
        myMethod = value
      End Set
    End Property

    Public Property Index() As Integer
      Get
        Return myIndex
      End Get
      Set(ByVal value As Integer)
        myIndex = value
      End Set
    End Property

    Sub New()

    End Sub
    Sub New(ByVal Index As Integer, ByVal Method As SelectOptions, ByVal ItemText As String)
      myIndex = Index
      myMethod = Method
      myItemText = ItemText
    End Sub
  End Class

  Private Sub myLbox_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles myLbox.GotFocus

    TempLogStart()
    Call DFocus()
    TempLogStop()
  End Sub

  Private Sub myLbox_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles myLbox.KeyDown

    TempLogStart()
    Call SelectItem(e.KeyCode)
    TempLogStop()
  End Sub

  Private Sub ProcessKeyEvents(ByVal e As KeyEventArgs)

    TempLogStart()
    Select Case e.KeyCode
      Case Is >= Keys.A And e.KeyCode <= Keys.Z
        MyBase.OnKeyUp(e)
      Case Keys.Back

      Case Keys.Enter

      Case Keys.Left, Keys.Right, Keys.Up, Keys.Down

      Case Is >= Keys.NumPad0 And e.KeyCode <= Keys.NumPad9, Is >= Keys.D0 And e.KeyCode <= Keys.D9

    End Select
    TempLogStop()
  End Sub

  Private Sub myLbox_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles myLbox.KeyPress
    If IsPrintChar(e.KeyChar) Then
      'Me.OnKeyPress(e)
      'Call MoveDrop()
    End If
    TempLogStop()
  End Sub

  Private Sub myLbox_KeyUp(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles myLbox.KeyUp
    If IsPrintChar(e.KeyValue) Then
      'Me.OnKeyUp(e)
      'Call MoveDrop()
    End If
    TempLogStop()
  End Sub

  Private Sub myLbox_LostFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles myLbox.LostFocus

    TempLogStart()
    Call DoHide(sender, e)
    TempLogStop()
  End Sub

  Private Sub myLbox_MouseClick(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles myLbox.MouseClick

    TempLogStart()
    'If e.Button <> Windows.Forms.MouseButtons.None Then
    Call SelectItem(SingleClick:=True)

    'End If
    TempLogStop()
  End Sub

  Private Sub myLbox_MouseDoubleClick(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles myLbox.MouseDoubleClick

    TempLogStart()
    'If e.Button <> Windows.Forms.MouseButtons.None Then
    Call SelectItem(DoubleClick:=True)

    'End If
    TempLogStop()
  End Sub

  Private Sub myForm_Deactivate(ByVal sender As Object, ByVal e As System.EventArgs) Handles myForm.Deactivate

    TempLogStart()
    Call TryHideFormWindowsDeactivated()
    TempLogStop()
  End Sub

  Private Sub myParentForm_Deactivate(ByVal sender As Object, ByVal e As System.EventArgs) Handles myParentForm.Deactivate

    TempLogStart()
    Call TryHideFormWindowsDeactivated()
    TempLogStop()
  End Sub

  Private Sub FocusTimer_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles FocusTimer.Tick

    TempLogStart()
    Me.Focus()
    TempLogStop()
  End Sub

  Public Sub New()

  End Sub

  Private Sub myLbox_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles myLbox.MouseDown
    myLbox_MouseClick(sender, e)
  End Sub
End Class

#End Region

Ответ 2

Вот версия С#. У него много вариантов.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            this.Load += new EventHandler(this.Form1_Load);

            InitializeComponent();
        }

    private clsCustomAutoCompleteTextbox ClsCustomAutoCompleteTextbox1 = null;

    private List<string> MasterList = new List<string> ();

    public void Form1_Load(object sender, System.EventArgs e) {
        this.ClsCustomAutoCompleteTextbox1 = new clsCustomAutoCompleteTextbox();

        this.ClsCustomAutoCompleteTextbox1.AutoCompleteFormBorder = System.Windows.Forms.FormBorderStyle.None;

        this.ClsCustomAutoCompleteTextbox1.AutoCompleteList = null;
        this.ClsCustomAutoCompleteTextbox1.Location = new System.Drawing.Point(27, 57);
        this.ClsCustomAutoCompleteTextbox1.Name = "clsCustomAutoCompleteTextbox1";
        this.ClsCustomAutoCompleteTextbox1.OnEnterSelect = true;
        this.ClsCustomAutoCompleteTextbox1.SelectionMethods = clsCustomAutoCompleteTextbox.SelectOptions.OnEnterSingleClick;
        this.ClsCustomAutoCompleteTextbox1.SelectTextAfterItemSelect = true;
        this.ClsCustomAutoCompleteTextbox1.ShowAutoCompleteOnFocus = false;
        this.ClsCustomAutoCompleteTextbox1.Size = new System.Drawing.Size(232, 20);
        this.ClsCustomAutoCompleteTextbox1.TabIndex = 0;

        this.Controls.Add(this.ClsCustomAutoCompleteTextbox1);

        this.ClsCustomAutoCompleteTextbox1.BeforeDisplayingAutoComplete +=
            new EventHandler<clsCustomAutoCompleteTextbox.clsAutoCompleteEventArgs>(BeforeDisplayingAutoComplete);

        List<string> L;
        L = new List<string>();
        L.Add("123123 - Bob");
        L.Add("534543 - Sally");
        L.Add("123123 - George");
        L.Add("34213 - Happy");
        MasterList = L;
        this.ClsCustomAutoCompleteTextbox1.AutoCompleteList = L;
    }

    private void BeforeDisplayingAutoComplete(object sender, clsCustomAutoCompleteTextbox.clsAutoCompleteEventArgs e) {
        string Name = this.ClsCustomAutoCompleteTextbox1.Text.ToLower();
        List<string> Display = new List<string> ();
        foreach (string Str in MasterList) {
            if ((Str.ToLower().IndexOf(Name) > -1)) {
                Display.Add(Str);
            }
        }
        e.AutoCompleteList = Display;
        e.SelectedIndex = 0;
    }
}
public class clsCustomAutoCompleteTextbox : TextBox
{
    private bool First = true;

    private object sender;

    private clsAutoCompleteEventArgs e;

    public List<string> test = new List<string> ();

    public int Tabs = 0;

    private int mSelStart;

    private int mSelLength;

    private List<string> myAutoCompleteList = new List<string> ();

    private ListBox myLbox = new ListBox();

    private Form myForm = new Form();

    private Form myParentForm;

    private bool DontHide = false;

    private bool SuspendFocus = false;

    private clsAutoCompleteEventArgs Args;

    private Timer HideTimer = new Timer();

    private Timer FocusTimer = new Timer();

    private bool myShowAutoCompleteOnFocus;

    private System.Windows.Forms.FormBorderStyle myAutoCompleteFormBorder = FormBorderStyle.None;

    private bool myOnEnterSelect;

    private int LastItem;

    private SelectOptions mySelectionMethods = (SelectOptions.OnDoubleClick | SelectOptions.OnEnterPress);

    private bool mySelectTextAfterItemSelect = true;

    private List<string> value;

    private int Cnt = 0;

    public bool SelectTextAfterItemSelect
    {
        get
        {
            return mySelectTextAfterItemSelect;
        }
        set
        {
            mySelectTextAfterItemSelect = value;
        }
    }

    [System.ComponentModel.Browsable(false)]
    public SelectOptions SelectionMethods
    {
        get
        {
            return mySelectionMethods;
        }
        set
        {
            mySelectionMethods = value;
        }
    }

    public bool OnEnterSelect
    {
        get
        {
            return myOnEnterSelect;
        }
        set
        {
            myOnEnterSelect = value;
        }
    }

    public System.Windows.Forms.FormBorderStyle AutoCompleteFormBorder
    {
        get
        {
            return myAutoCompleteFormBorder;
        }
        set
        {
            myAutoCompleteFormBorder = value;
        }
    }

    public bool ShowAutoCompleteOnFocus
    {
        get
        {
            return myShowAutoCompleteOnFocus;
        }
        set
        {
            myShowAutoCompleteOnFocus = value;
        }
    }

    public ListBox Lbox
    {
        get
        {
            return myLbox;
        }
    }

    public List<string> AutoCompleteList { get; set; }

    public event EventHandler<clsAutoCompleteEventArgs> BeforeDisplayingAutoComplete;

    public event EventHandler<clsItemSelectedEventArgs> ItemSelected;

    public enum SelectOptions
    {
        None = 0,

        OnEnterPress = 1,

        OnSingleClick = 2,

        OnDoubleClick = 4,

        OnTabPress = 8,

        OnRightArrow = 16,

        OnEnterSingleClick = 3,

        OnEnterSingleDoubleClicks = 7,

        OnEnterDoubleClick = 5,

        OnEnterTab = 9,
    }

    public class clsAutoCompleteEventArgs : EventArgs
    {

        private List<string> myAutoCompleteList;

        private bool myCancel;

        private int mySelectedIndex;

        private List<string> value;

        public int SelectedIndex
        {
            get
            {
                return mySelectedIndex;
            }
            set
            {
                mySelectedIndex = value;
            }
        }

        public bool Cancel
        {
            get
            {
                return myCancel;
            }
            set
            {
                myCancel = value;
            }
        }
        public List<string> AutoCompleteList { get; set; }
    }

    public override string SelectedText
    {
        get
        {
            return base.SelectedText;
        }
        set
        {
            base.SelectedText = value;
        }
    }

    public override int SelectionLength
    {
        get
        {
            return base.SelectionLength;
        }
        set
        {
            base.SelectionLength = value;
        }
    }

    public clsCustomAutoCompleteTextbox()
    {
        HideTimer.Tick += new EventHandler(HideTimer_Tick);
        FocusTimer.Tick += new EventHandler(FocusTimer_Tick);

        myLbox.Click += new EventHandler(myLbox_Click);
        myLbox.DoubleClick += new EventHandler(myLbox_DoubleClick);
        myLbox.GotFocus += new EventHandler(myLbox_GotFocus);
        myLbox.KeyDown += new KeyEventHandler(myLbox_KeyDown);

        myLbox.KeyUp += new KeyEventHandler(myLbox_KeyUp);
        myLbox.LostFocus += new EventHandler(myLbox_LostFocus);
        myLbox.MouseClick += new MouseEventHandler(myLbox_MouseClick);
        myLbox.MouseDoubleClick += new MouseEventHandler(myLbox_MouseDoubleClick);
        myLbox.MouseDown += new MouseEventHandler(myLbox_MouseDown);


        this.GotFocus += new EventHandler(clsCustomAutoCompleteTextbox_GotFocus);
        this.KeyDown += new KeyEventHandler(clsCustomAutoCompleteTextbox_KeyDown);
        this.Leave += new EventHandler(clsCustomAutoCompleteTextbox_Leave);
        this.LostFocus += new EventHandler(clsCustomAutoCompleteTextbox_LostFocus);
        this.Move += new EventHandler(clsCustomAutoCompleteTextbox_Move);
        this.ParentChanged += new EventHandler(clsCustomAutoCompleteTextbox_ParentChanged);


    }

    override protected void OnKeyUp(System.Windows.Forms.KeyEventArgs e)
    {


        base.OnKeyUp(e);
        ShowOnChar(new string(((char)(e.KeyValue)),1));
    }

    private void ShowOnChar(string C)
    {


        if (IsPrintChar(C))
        {
            this.ShowAutoComplete();
        }
    }

    private bool IsPrintChar(int C)
    {


        return IsPrintChar(((char)(C)));
    }

    private bool IsPrintChar(byte C)
    {


        return IsPrintChar(((char)(C)));
    }

    private bool IsPrintChar(char C)
    {


        return IsPrintChar(C.ToString());
    }

    private bool IsPrintChar(string C)
    {

        if (System.Text.RegularExpressions.Regex.IsMatch(C, "[^\\t\\n\\r\\f\\v]"))
        {
            return true;
        }
        else
        {
            return false;
        }

    }

    private void clsCustomAutoCompleteTextbox_GotFocus(object sender, System.EventArgs e)
    {

        if ((!this.SuspendFocus
                    && (this.myShowAutoCompleteOnFocus
                    && (this.myForm.Visible == false))))
        {
            this.ShowAutoComplete();
        }

    }

    private void clsCustomAutoCompleteTextbox_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
    {

        if (!SelectItem(e.KeyCode, false, false))
        {
            if ((e.KeyCode == Keys.Up))
            {
                if ((myLbox.SelectedIndex > 0))
                {
                    MoveLBox((myLbox.SelectedIndex - 1));
                }
            }
            else if ((e.KeyCode == Keys.Down))
            {
                MoveLBox((myLbox.SelectedIndex + 1));
            }
        }

    }

    new void SelectAll()
    {
    }

    private void MoveLBox(int Index)
    {

        try
        {
            if ((Index
                        > (myLbox.Items.Count - 1)))
            {
                Index = (myLbox.Items.Count - 1);
            }
            myLbox.SelectedIndex = Index;
        }
        catch
        {
        }

    }

    private void clsCustomAutoCompleteTextbox_Leave(object sender, System.EventArgs e)
    {

        DoHide(sender, e);

    }

    private void clsCustomAutoCompleteTextbox_LostFocus(object sender, System.EventArgs e)
    {

        DoHide(sender, e);

    }

    private void clsCustomAutoCompleteTextbox_Move(object sender, System.EventArgs e)
    {

        MoveDrop();

    }

    private void clsCustomAutoCompleteTextbox_ParentChanged(object sender, System.EventArgs e)
    {

        if (myParentForm != null) myParentForm.Deactivate -= new EventHandler(myParentForm_Deactivate);
        myParentForm = GetParentForm(this);
        if (myParentForm != null) myParentForm.Deactivate += new EventHandler(myParentForm_Deactivate);
    }

    private void HideTimer_Tick(object sender, System.EventArgs e)
    {

        MoveDrop();
        DoHide(sender, e);
        Cnt++;
        if ((Cnt > 300))
        {
            if (!AppHasFocus(""))
            {
                DoHideAuto();
            }
            Cnt = 0;
        }

    }

    private void myLbox_Click(object sender, System.EventArgs e)
    {
    }

    private void myLbox_DoubleClick(object sender, System.EventArgs e)
    {
    }

    private bool SelectItem(Keys Key, bool SingleClick)
    {
        return SelectItem(Key, SingleClick, false);
    }

    private bool SelectItem(Keys Key)
    {
        return SelectItem(Key, false, false);
    }

    private bool SelectItem(Keys Key, bool SingleClick, bool DoubleClick)
    {

        // Warning!!! Optional parameters not supported
        // Warning!!! Optional parameters not supported
        // Warning!!! Optional parameters not supported
        bool DoSelect = true;
        SelectOptions Meth = SelectOptions.None;
        LastItem = -1;

        if (((this.mySelectionMethods & SelectOptions.OnEnterPress) > 0) && (Key == Keys.Enter))
        {
            Meth = SelectOptions.OnEnterPress;
        }
        else if (((this.mySelectionMethods & SelectOptions.OnRightArrow) > 0) && Key == Keys.Right)
        {
            Meth = SelectOptions.OnRightArrow;
        }
        else if (((this.mySelectionMethods & SelectOptions.OnTabPress) > 0) && Key == Keys.Tab)
        {
            Meth = SelectOptions.OnTabPress;
        }
        else if (((this.mySelectionMethods & SelectOptions.OnSingleClick) > 0) && SingleClick)
        {
            Meth = SelectOptions.OnEnterPress;
        }
        else if (((this.mySelectionMethods & SelectOptions.OnDoubleClick) > 0) && DoubleClick)
        {
            Meth = SelectOptions.OnEnterPress;
        }
        else
        {
            DoSelect = false;
        }

        LastItem = myLbox.SelectedIndex;
        if (DoSelect)
        {
            DoSelectItem(Meth);
        }

        return DoSelect;
    }
    public class clsItemSelectedEventArgs : EventArgs
    {

        private int myIndex;

        private SelectOptions myMethod;

        private string myItemText;

        public clsItemSelectedEventArgs()
        {
        }

        public clsItemSelectedEventArgs(int Index, SelectOptions Method, string ItemText)
        {
            myIndex = Index;
            myMethod = Method;
            myItemText = ItemText;
        }

        public string ItemText
        {
            get
            {
                return myItemText;
            }
            set
            {
                myItemText = value;
            }
        }

        public SelectOptions Method
        {
            get
            {
                return myMethod;
            }
            set
            {
                myMethod = value;
            }
        }

        public int Index
        {
            get
            {
                return myIndex;
            }
            set
            {
                myIndex = value;
            }
        }
    }

        [System.Runtime.InteropServices.DllImport("user32.dll")]
        static extern IntPtr GetForegroundWindow();

        [System.Runtime.InteropServices.DllImport("user32.dll")]
        static extern int GetWindowThreadProcessId(IntPtr hWnd, ref int ProcessID);

        private bool AppHasFocus(string ExeNameWithoutExtension)
        {
            bool Out = false;
            // Warning!!! Optional parameters not supported
            int PID = 0;

            if ((ExeNameWithoutExtension == ""))
            {
                ExeNameWithoutExtension = System.Diagnostics.Process.GetCurrentProcess().ProcessName;
            }
            IntPtr activeHandle = GetForegroundWindow();
            GetWindowThreadProcessId(activeHandle, ref PID);
            if ((PID > 0))
            {
                // For Each p As Process In Process.GetProcessesByName(ExeNameWithoutExtension)
                if ((PID == System.Diagnostics.Process.GetCurrentProcess().Id))
                {
                    Out = true;
                }
                //  Next
            }

            return Out;
        }

        private void SaveSelects()
        {
            this.mSelStart = this.SelectionStart;
            this.mSelLength = this.SelectionLength;
        }

        private void LoadSelects()
        {
            this.SelectionStart = this.mSelStart;
            this.SelectionLength = this.mSelLength;
        }

        private void ShowAutoComplete()
        {

            Args = new clsAutoCompleteEventArgs();
            // With...
            Args.Cancel = false;
            Args.AutoCompleteList = this.myAutoCompleteList;
            if ((myLbox.SelectedIndex == -1))
            {
                Args.SelectedIndex = 0;
            }
            else
            {
                Args.SelectedIndex = myLbox.SelectedIndex;
            }

            if (BeforeDisplayingAutoComplete != null) BeforeDisplayingAutoComplete(this, Args);
            this.myAutoCompleteList = Args.AutoCompleteList;
            // If Me.myAutoCompleteList IsNot Nothing AndAlso Me.myAutoCompleteList.Count - 1 < Args.SelectedIndex Then
            //   Args.SelectedIndex = Me.myAutoCompleteList.Count - 1
            // End If
            if ((!Args.Cancel && (Args.AutoCompleteList != null) && Args.AutoCompleteList.Count > 0))
            {
                DoShowAuto();
            }
            else
            {
                DoHideAuto();
            }

        }

        private void DoShowAuto()
        {
            SaveSelects();

            myLbox.BeginUpdate();
            try
            {
                myLbox.Items.Clear();
                myLbox.Items.AddRange(this.myAutoCompleteList.ToArray());
                this.MoveLBox(Args.SelectedIndex);
            }
            catch (Exception ex)
            {
            }
            myLbox.EndUpdate();
            myParentForm = GetParentForm(this);
            if (myParentForm != null)
            {
                myLbox.Name = ("mmmlbox" + DateTime.Now.Millisecond);
                if ((myForm.Visible == false))
                {
                    myForm.Font = this.Font;
                    myLbox.Font = this.Font;
                    myLbox.Visible = true;
                    myForm.Visible = false;
                    myForm.ControlBox = false;
                    myForm.Text = "";
                    if (First)
                    {
                        myForm.Width = this.Width;
                        myForm.Height = 200;
                    }
                    First = false;
                    if (!myForm.Controls.Contains(myLbox))
                    {
                        myForm.Controls.Add(myLbox);
                    }
                    myForm.FormBorderStyle = FormBorderStyle.None;
                    myForm.ShowInTaskbar = false;
                    // With...
                    myLbox.Dock = DockStyle.Fill;
                    myLbox.SelectionMode = SelectionMode.One;
                    // Frm.Controls.Add(myLbox)
                    DontHide = true;
                    SuspendFocus = true;
                    myForm.TopMost = true;
                    myForm.FormBorderStyle = this.myAutoCompleteFormBorder;
                    myForm.BringToFront();
                    MoveDrop();
                    myForm.Visible = true;
                    myForm.Show();
                    MoveDrop();
                    HideTimer.Interval = 10;
                    this.Focus();
                    SuspendFocus = false;
                    HideTimer.Enabled = true;
                    DontHide = false;
                    LoadSelects();
                }
            }

        }

        void MoveDrop()
        {

            Point Pnt = new Point(this.Left, (this.Top
                            + (this.Height + 2)));
            Point ScreenPnt = this.PointToScreen(new Point(-2, this.Height));
            // Dim FrmPnt As Point = Frm.PointToClient(ScreenPnt)
            if (myForm != null)
            {
                myForm.Location = ScreenPnt;
                // myForm.BringToFront()
                // myForm.Focus()
                // myLbox.Focus()
                // Me.Focus()
            }

        }

        void DoHide(object sender, EventArgs e)
        {

            HideAuto();

        }

        private void DFocus(int Delay)
        {

            // Warning!!! Optional parameters not supported
            FocusTimer.Interval = Delay;
            FocusTimer.Start();

        }

        private void DFocus()
        {
            DFocus(10);
        }

        private void DoHideAuto()
        {

            myForm.Hide();
            HideTimer.Enabled = false;
            FocusTimer.Enabled = false;

        }

        private void HideAuto()
        {

            if ((myForm.Visible && HasLostFocus()))
            {
                DoHideAuto();
            }

        }

        private bool HasLostFocus()
        {

            bool Out = false;
            if (this.myForm == null || myForm.ActiveControl != this.myLbox)
            {
                Out = true;
            }
            if (this.myParentForm == null || this.myParentForm.ActiveControl != this)
            {
                Out = true;
            }

            return Out;
        }

        private Form GetParentForm(Control InCon)
        {

            Control TopCon = FindTopParent(InCon);
            Form Out = null;
            if ((TopCon is Form))
            {
                Out = ((Form)(TopCon));
            }

            return Out;
        }

        private Control FindTopParent(Control InCon)
        {

            Control Out;
            if ((InCon.Parent == null))
            {
                Out = InCon;
            }
            else
            {
                Out = FindTopParent(InCon.Parent);
            }

            return Out;
        }

        private void DoSelectItem(SelectOptions Method)
        {

            if (((this.myLbox.Items.Count > 0)
                        && (this.myLbox.SelectedIndex > -1)))
            {
                string Value = this.myLbox.SelectedItem.ToString();
                string Orig = this.Text;
                this.Text = Value;
                if (mySelectTextAfterItemSelect)
                {
                    try
                    {
                        this.SelectionStart = Orig.Length;
                        this.SelectionLength = (Value.Length - Orig.Length);
                    }
                    catch (Exception ex)
                    {
                    }
                }
                else
                {
                    // Me.SelectionStart = Me.Text.Length
                    // Me.SelectionLength = 0
                }

                clsItemSelectedEventArgs a;
                a = new clsItemSelectedEventArgs();
                a.Index = this.myLbox.SelectedIndex;
                a.Method = Method;
                a.ItemText = Value;

                if (ItemSelected != null) ItemSelected(this, a);

                //ItemSelected(this, new clsItemSelectedEventArgs(this.myLbox.SelectedIndex, Method, Value));
                this.DoHideAuto();
            }

        }

        private void myLbox_GotFocus(object sender, System.EventArgs e)
        {

            DFocus();

        }

        private void myLbox_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
        {

            SelectItem(e.KeyCode);

        }

        private void ProcessKeyEvents(KeyEventArgs e)
        {


                if ((e.KeyCode >= Keys.A) && (e.KeyCode <= Keys.Z))
                    base.OnKeyUp(e);


                //Keys.Back;
                //Keys.Enter;
                //Keys.Left;
                //Keys.Right;
                //Keys.Up;
                //Keys.Down;
                //(Keys.NumPad0 & (e.KeyCode <= Keys.NumPad9));
                //(Keys.D0 & (e.KeyCode <= Keys.D9));


        }

        private void myLbox_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
        {
            if (IsPrintChar(e.KeyChar))
            {
                // Me.OnKeyPress(e)
                // Call MoveDrop()
            }

        }

        private void myLbox_KeyUp(object sender, System.Windows.Forms.KeyEventArgs e)
        {
            if (IsPrintChar(e.KeyValue))
            {
                // Me.OnKeyUp(e)
                // Call MoveDrop()
            }

        }

        private void myLbox_LostFocus(object sender, System.EventArgs e)
        {

            DoHide(sender, e);

        }

        private void myLbox_MouseClick(object sender, System.Windows.Forms.MouseEventArgs e)
        {

            // If e.Button <> Windows.Forms.MouseButtons.None Then
            SelectItem(Keys.None,true);
            // End If

        }

        private void myLbox_MouseDoubleClick(object sender, System.Windows.Forms.MouseEventArgs e)
        {

            // If e.Button <> Windows.Forms.MouseButtons.None Then
            SelectItem(Keys.None, false, true);
            // End If

        }

        private void myForm_Deactivate(object sender, System.EventArgs e)
        {


        }

        private void myParentForm_Deactivate(object sender, System.EventArgs e)
        {


        }

        private void FocusTimer_Tick(object sender, System.EventArgs e)
        {

            this.Focus();

        }

        private void myLbox_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            myLbox_MouseClick(sender, e);
        }
    }
}

Ответ 3

Я не знаю, является ли это вариантом, но, например, вы могли бы сделать что-то вроде этого:

    private void Main_Load(object sender, EventArgs e)
    {
        DataTable dt = new DataTable();
        dt.Columns.Add("colCustomers", typeof(string));
        dt.Rows.Add(new object[] { "1 John" });
        dt.Rows.Add(new object[] { "2 Kate" });
        dt.Rows.Add(new object[] { "3 Jill" });

        comboBox1.DataSource = dt.DefaultView; //allows us to filter the results
        comboBox1.DisplayMember = "Col1";
    }

    private void comboBox1_TextChanged(object sender, EventArgs e)
    {
        if (comboBox1.SelectedIndex == -1)
        {
            dt.DefaultView.RowFilter = "colCustomers LIKE '%" + comboBox1.Text + "%'";
        }
    }

Конечно, вы можете также использовать поиск и позиционирование вместо фильтрации, но, поскольку, вероятно, многие клиенты, я думал, что лучше оставить только тех клиентов, которые соответствуют. Когда пользователь удаляет свою запись, он должен отображать всех снова. Возможно, код может быть полезен для некоторых настроек, но вам придется экспериментировать, чтобы придумать то, что вы хотели.

Ответ 4

вы можете использовать этот класс:

public partial class MyComboBox : ComboBox
    {

        private IList<object> collectionList = null;

        public MyComboBox()
        {
            InitializeComponent();
            collectionList = new List<object>();

        }
        public MyComboBox(IContainer container)
            : this()
        {
            container.Add(this);
        }

        protected override void OnTextUpdate(EventArgs e)
        {
            try
            {
                //base.OnTextUpdate(e);
                IList<object> values = collectionList
                 .Where(x => x.ToString().ToLower().Contains(Text.ToLower()))
                 .ToList();

                //Don't use Items.Clear() because the selectionstart resets to Zero
                while (Items.Count > 0)
                {
                    Items.RemoveAt(0);
                }

                this.Items.AddRange(values.ToArray());

                this.DroppedDown = true;
                Cursor.Current = Cursors.Default;
            }
            catch(Exception ex)
            {
                SelectedIndex = -1;
                //MessageBox.Show(ex.Message);
            }

        }

        protected override void OnTextChanged(EventArgs e)
        {
            //base.OnTextChanged(e);
            if (this.Text == string.Empty)
            {
                Items.Clear();
                this.Items.AddRange(collectionList.ToArray());
            }
        }

        protected override void OnBindingContextChanged(EventArgs e)
        {
            base.OnBindingContextChanged(e);
            collectionList = this.Items.OfType<object>().ToList();
        }
    }

Ответ 5

Вот мой код для combobox с привязкой к базе данных (в моем случае DB Access). Вы добавляете в форму combobox и listbox. Затем используйте мой код ниже как ссылку, как показано на рисунке:

  • Как обновить комбобокс databound
  • Добавить обработчики событий таким образом, чтобы когда вы используете клавиши со стрелками в выпадающем списке, он проходит через приводит к списку.
  • Используйте таймер для ограничения запросов к базе данных только когда прошло 500 мс с момента последнего нажатия клавиши.

Я уверен, что есть лучшие способы сделать некоторые из этого. Этот код "работает для меня". Критика оценена.

    #region AutoComplete Organization Box

    System.Windows.Forms.Timer mOrganizationTextChangedTimer = null;
    void organizationComboBox_TextChanged(object sender, System.EventArgs e)
    {
        if (mOrganizationTextChangedTimer == null)
        {
            mOrganizationTextChangedTimer = new System.Windows.Forms.Timer();
            mOrganizationTextChangedTimer.Interval = 500;
            mOrganizationTextChangedTimer.Tick += new EventHandler(mOrganizationTextChangedTimer_Tick);
        }
        mOrganizationTextChangedTimer.Enabled = true;
    }

    void mOrganizationTextChangedTimer_Tick(object sender, EventArgs e)
    {
        mOrganizationTextChangedTimer.Enabled = false;
        UpdateOrganizationNameAutocompleteResults( comboBoxOrganizationName.Text );    
    }

    void UpdateOrganizationNameAutocompleteResults( string pSearchString ) 
    {
        listBoxOrganizationAutocompleteResults.Items.Clear();
        if (comboBoxOrganizationName.Text.Length == 0)
        {
            HideOrganizationNameAutocompleteResults();
            return;
        }

        // Added a custom query to search our database and return results that match.  The query uses UCase on the columns.
        allertDataSet3.OrganizationDataTable orgs = organizationTableAdapter.GetDataByOrganizationNameSearchUCase("%" + pSearchString.ToUpper() + "%", "%" + pSearchString.ToUpper() + "%");

        foreach( allertDataSet3.OrganizationRow r in orgs ) {
            string longName = r.OrganizationName;
            listBoxOrganizationAutocompleteResults.Items.Add(longName);
            listBoxOrganizationAutocompleteResults.Visible = true;
            listBoxOrganizationAutocompleteResults.BringToFront();
        }

        // This Code block is needed because once you select an organization, the combobox text changes which forces another search.
        // There is only one result from that search so this hides it when the search result equals the already selected combobox.
        try {
            System.Data.DataRowView drv = (System.Data.DataRowView) comboBoxOrganizationName.SelectedItem;
            allertDataSet3.OrganizationRow orgRow = (allertDataSet3.OrganizationRow)drv.Row;

            if ( listBoxOrganizationAutocompleteResults.Items.Count == 1 && 
                ((string)listBoxOrganizationAutocompleteResults.Items[0]).Equals(orgRow.OrganizationName) )
            {
                HideOrganizationNameAutocompleteResults();
            }
        }
        catch {
            // do nothing
        }            
    }

    void organizationComboBoxAutocompleteResults_SelectedIndexChanged(object sender, System.EventArgs e)
    {
        foreach (System.Data.DataRowView drv in comboBoxOrganizationName.Items)
        {
            Alertus.Allert.allertDataSet3.OrganizationRow orgRow = (Alertus.Allert.allertDataSet3.OrganizationRow)drv.Row;
            if (orgRow.OrganizationName.Equals((string) listBoxOrganizationAutocompleteResults.SelectedItem))
            {
                // Prevents it from searching again.
                comboBoxOrganizationName.TextChanged -= organizationComboBox_TextChanged;
                comboBoxOrganizationName.SelectedItem = drv;
                comboBoxOrganizationName.TextChanged += organizationComboBox_TextChanged;
                HideOrganizationNameAutocompleteResults();
                return;
            }
        }

        // This is basically an error... it should have found it.
        HideOrganizationNameAutocompleteResults();
    }

    void listBoxOrganizationAutocompleteResults_LostFocus(object sender, System.EventArgs e)
    {
        HideOrganizationNameAutocompleteResults();
    }

    void HideOrganizationNameAutocompleteResults()
    {
        listBoxOrganizationAutocompleteResults.Visible = false;
    }

    private void listBoxOrganizationAutocompleteResults_MouseClick(object sender, MouseEventArgs e)
    {
        // When mouse is clicked we assume user made a seletion.
        organizationComboBoxAutocompleteResults_SelectedIndexChanged(null, null);
    }

    /// <summary>
    /// Redirects the Arrow keys to update the selected index in the autocomplete list box.
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    private void comboBoxOrganizationName_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.KeyCode == Keys.Up)
        {
            if (listBoxOrganizationAutocompleteResults.Items.Count >= 1 && listBoxOrganizationAutocompleteResults.Visible)
            {
                if (listBoxOrganizationAutocompleteResults.SelectedIndex < 0)
                {
                    listBoxOrganizationAutocompleteResults.SelectedIndex = 0;
                }
                else
                {
                    listBoxOrganizationAutocompleteResults.SelectedIndex = (listBoxOrganizationAutocompleteResults.SelectedIndex - 1) % listBoxOrganizationAutocompleteResults.Items.Count;
                }
            }
            e.Handled = true;
        }
        else if (e.KeyCode == Keys.Down)
        {
            if (listBoxOrganizationAutocompleteResults.Items.Count >= 1 && listBoxOrganizationAutocompleteResults.Visible )
            {
                if (listBoxOrganizationAutocompleteResults.SelectedIndex < 0)
                {

                    listBoxOrganizationAutocompleteResults.SelectedIndex = 0;
                }
                else
                {
                    listBoxOrganizationAutocompleteResults.SelectedIndex = (listBoxOrganizationAutocompleteResults.SelectedIndex + 1) % listBoxOrganizationAutocompleteResults.Items.Count;
                }
            }

            e.Handled = true;
        }
        else if (e.KeyCode == Keys.Enter)
        {
            e.Handled = true;
            if (listBoxOrganizationAutocompleteResults.Visible)
            {
                organizationComboBoxAutocompleteResults_SelectedIndexChanged(null, null);
            }
        }
    }

    #endregion

Код конструктора:

    // 
    // comboBoxOrganizationName
    // 
    this.comboBoxOrganizationName.FormattingEnabled = true;
    this.comboBoxOrganizationName.Location = new System.Drawing.Point(19, 53);
    this.comboBoxOrganizationName.Name = "comboBoxOrganizationName";
    this.comboBoxOrganizationName.Size = new System.Drawing.Size(363, 21);
    this.comboBoxOrganizationName.TabIndex = 1;
    this.comboBoxOrganizationName.SelectedIndexChanged += new System.EventHandler(this.comboBoxOrganizationName_SelectedIndexChanged);
    this.comboBoxOrganizationName.Enter += new System.EventHandler(this.comboBoxOrganizationName_Enter);
    this.comboBoxOrganizationName.KeyDown += new System.Windows.Forms.KeyEventHandler(this.comboBoxOrganizationName_KeyDown);
    this.comboBoxOrganizationName.TextChanged += new System.EventHandler(this.organizationComboBox_TextChanged);**

  // 
            // listBoxOrganizationAutocompleteResults
            // 
            this.listBoxOrganizationAutocompleteResults.FormattingEnabled = true;
            this.listBoxOrganizationAutocompleteResults.Location = new System.Drawing.Point(20, 76);
            this.listBoxOrganizationAutocompleteResults.Name = "listBox1";
            this.listBoxOrganizationAutocompleteResults.Size = new System.Drawing.Size(359, 95);
            this.listBoxOrganizationAutocompleteResults.TabIndex = 19;
            this.listBoxOrganizationAutocompleteResults.Visible = false;
            this.listBoxOrganizationAutocompleteResults.MouseClick += new System.Windows.Forms.MouseEventHandler(this.listBoxOrganizationAutocompleteResults_MouseClick);
            this.listBoxOrganizationAutocompleteResults.Leave += new System.EventHandler(this.listBoxOrganizationAutocompleteResults_LostFocus);