Private Sub FindAllOfMyString(ByVal searchString As String)
   ' Set the SelectionMode property of the ListBox to select multiple items.
   listBox1.SelectionMode = SelectionMode.MultiExtended

   ' Set our intial index variable to -1.
   Dim x As Integer = -1
   ' If the search string is empty exit.
   If searchString.Length <> 0 Then
      ' Loop through and find each item that matches the search string.
      Do
         ' Retrieve the item based on the previous index found. Starts with -1 which searches start.
         x = listBox1.FindString(searchString, x)
         ' If no item is found that matches exit.
         If x <> -1 Then
            ' Since the FindString loops infinitely, determine if we found first item again and exit.
            If ListBox1.SelectedIndices.Count > 0 Then
               If x = ListBox1.SelectedIndices(0) Then
                  Return
               End If
            End If
            ' Select the item in the ListBox once it is found.
            ListBox1.SetSelected(x, True)
         End If
      Loop While x <> -1
   End If
End Sub

' 导入命名空间
Imports System.Drawing
Imports System.Drawing.Drawing2D
Imports System.Windows.Forms

public class ListBoxMultiSelectionIndex
   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

        TextBox2.Text = "Here are the selected indices: "
        For Each Index In ListBox1.SelectedIndices
            TextBox2.Text &= Index.ToString() & " "
        Next

    End Sub

End Class