Private Sub TextBoxHöhe_MouseHover(ByVal sender As Object, ByVal e As _
      System.EventArgs) Handles TextBoxHöhe.MouseHover
        TextBoxHöhe.Enabled = True
    End Sub
 
    Private Sub TextBoxHöhe_MouseLeave(ByVal sender As Object, ByVal e As _
      System.EventArgs) Handles TextBoxHöhe.MouseLeave
        If TextBoxHöhe.Text = "" Then
            TextBoxHöhe.Enabled = False
        End If
    End Sub

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