'Beispiel: VB .Net - ListBox - Pruefen ob ein bestimmter Eintrag ausgewaehlt wurde ' Option Explicit On Option Strict On Public Class Form1 Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) _ Handles MyBase.Load Me.CenterToScreen() Dim s() As String = {"Hello", "World", "Greetings"} Me.ListBox1.Items.AddRange(s) Me.TextBox1.Text = s(0) End Sub Private Sub ListBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) _ Handles ListBox1.SelectedIndexChanged Dim Result As Boolean = Me.IsItemSelected(Me.TextBox1.Text) Select Case Result Case Is = True Me.Text = "Der gewaehlte Eintrag stimmt ueberein" Case Else Me.Text = "Keine Uebereinstimmung gefunden" End Select End Sub Private Function IsItemSelected(ByVal Description As String) As Boolean Dim Success As Boolean = False If Me.ListBox1.SelectedIndex < 0 Then Return Success Else Try Dim Item As String = Me.ListBox1.SelectedItem.ToString() If Item = Description Then Success = True Return Success End If Catch ex As Exception MessageBox.Show(ex.Message.ToString(), "Info") End Try End If Return Success End Function End Class