Private Index As Integer
 
  ' Suchen ab Anfang
  Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
    System.EventArgs) Handles Button1.Click
    Index = 0
    SearchString()
  End Sub
 
  ' Weitersuchen
  Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As _
    System.EventArgs) Handles Button2.Click
    SearchString()
  End Sub
 
  ' Rückwärts suchen
  Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As _
    System.EventArgs) Handles Button3.Click
    SearchStringRevers()
  End Sub
 
  ' Vorwärtssuche
  Private Sub SearchString()
    With Me.Content
      Dim i As Integer = .Find(Me.TextBox1.Text, Index + 1, _
        RichTextBoxFinds.WholeWord)
      If i < 0 Then
        MsgBox("Ende erreicht!", MsgBoxStyle.Information)
      Else
        Index = i
      End If
      .Focus()
    End With
  End Sub
 
  ' Rückwärtssuche
  Private Sub SearchStringRevers()
    With Me.Content
      Dim i As Integer = .Find(Me.TextBox1.Text, 0, Index - 1, _
        RichTextBoxFinds.WholeWord Or RichTextBoxFinds.Reverse)
      If i < 0 Then
        MsgBox("Anfang erreicht!", MsgBoxStyle.Information)
      Else
        Index = i
      End If
      .Focus()
    End With
  End Sub