Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As _
      System.Windows.Forms.PaintEventArgs) Handles Me.Paint
 
        Dim txtmark As New Textmark()
        Dim c As Control
        For Each c In Me.Controls
            If TypeOf c Is TextBox Then
                txtmark.Text_markieren = True
            End If
        Next
   End Sub

Public Class Textmark
 
    ' erben von System.Windows.Forms.TextBox
    Inherits System.Windows.Forms.TextBox
 
    Private _Text_markieren As Boolean = True ' Text markieren erlaubt Ja/Nein
 
    Public Property Text_markieren() As Boolean
        Get
            Return _Text_markieren
        End Get
        Set(ByVal Value As Boolean)
            _Text_markieren = Value
        End Set
    End Property
 
    Public Function Textmarkieren() As Boolean
        ' *****************************************************
        ' * RETURN Boolean
        ' *   True:  Text markiern ist OK
        ' *   False: Text markiern nicht OK         
        ' *****************************************************
 
        If _Text_markieren = True Then
            Me.SelectionStart = 0
            Me.SelectionLength = Me.Text
        End If
    End Function
 
End Class

fg viperbone