Hello,
now I solve the problem with your help:
So the VisualTreeHelper say me, the parent of the parent of my button is a System.Windows.Controls.GridViewRowPresenter I do this:
Dim myGrid As GridViewRowPresenter
Dim LstRow As DataRowView
myGrid = VisualTreeHelper.GetParent(VisualTreeHelper.GetParent(sender))
Me.m_PlanRow = CType(myGrid.Content, DataRowView)
strText = LstRow("ANZAHL") & " " & LstRow("ERR_CODE")
...
Thanks
Peter :)