VB.NET ListBox.SelectedIndexChanged事件代碼示例

Private Sub listBox1_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles listBox1.SelectedIndexChanged
   ' Get the currently selected item in the ListBox.
   Dim curItem As String = listBox1.SelectedItem.ToString()

   ' Find the string in ListBox2.
   Dim index As Integer = listBox2.FindString(curItem)
   ' If the item was not found in ListBox 2 display a message box, otherwise select it in ListBox2.
   If index = -1 Then
      MessageBox.Show("Item is not available in ListBox2")
   Else
      listBox2.SetSelected(index, True)
   End If
End Sub

' 導入命名空間
Imports System.Drawing
Imports System.Drawing.Drawing2D
Imports System.Windows.Forms

public class ListBoxMultiSelection
   public Shared Sub Main
        Application.Run(New Form1)
   End Sub
End class

Public Class Form1
    Inherits System.Windows.Forms.Form

#Region " Windows Form Designer generated code "

    Public Sub New()
        MyBase.New()

        'This call is required by the Windows Form Designer.
        InitializeComponent()

        'Add any initialization after the InitializeComponent() call

    End Sub

    'Form overrides dispose to clean up the component list.
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    'Required by the Windows Form Designer
    Private components As System.ComponentModel.IContainer

    'NOTE: The following procedure is required by the Windows Form Designer
    'It can be modified using the Windows Form Designer.  
    'Do not modify it using the code editor.
    Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
    Friend WithEvents TextBox2 As System.Windows.Forms.TextBox

    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.TextBox1 = New System.Windows.Forms.TextBox
        Me.TextBox2 = New System.Windows.Forms.TextBox
        Me.SuspendLayout()
        '
        'TextBox1
        '
        Me.TextBox1.Location = New System.Drawing.Point(8, 184)
        Me.TextBox1.Name = "TextBox1"
        Me.TextBox1.Size = New System.Drawing.Size(272, 20)
        Me.TextBox1.TabIndex = 0
        Me.TextBox1.Text = ""
        '
        'TextBox2
        '
        Me.TextBox2.Location = New System.Drawing.Point(8, 240)
        Me.TextBox2.Name = "TextBox2"
        Me.TextBox2.Size = New System.Drawing.Size(272, 20)
        Me.TextBox2.TabIndex = 1
        Me.TextBox2.Text = ""

        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.ClientSize = New System.Drawing.Size(292, 273)
        Me.Controls.Add(Me.TextBox2)
        Me.Controls.Add(Me.TextBox1)
        Me.ResumeLayout(False)

        ListBox1 = New ListBox
        ListBox1.Size = New Size(270, 100)
        ListBox1.Location = New Point(10, 60)
        AddHandler ListBox1.SelectedIndexChanged, AddressOf ListBox1_SelectedIndexChanged
        Me.Controls.Add(ListBox1)
        ListBox1.MultiColumn = True
        ListBox1.SelectionMode = SelectionMode.MultiExtended

        For i As Integer = 0 To 19
            ListBox1.Items.Add("Item " & i.ToString())
        Next i

        ListBox1.SetSelected(2, True)
        ListBox1.SetSelected(4, True)
        ListBox1.SetSelected(8, True)
        ListBox1.SetSelected(10, True)

    End Sub

#End Region
    Dim ListBox1 As ListBox


    Private Sub ListBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
        Dim Item As String
        Dim Index As Integer

        TextBox1.Text = "Here are the selected items: "
        For Each Item In ListBox1.SelectedItems
            TextBox1.Text &= Item.ToString() & " "
        Next

    End Sub

End Class