DataGrid Column width

I have inherited DataGrid to a new myDG class but I had to override mousedown. In MouseDown I added code that first checks if the mouse is on grid's cell: If (hti.Type = DataGrid.HitTestType.Cell) Then Dim e1 As MouseEventArgs e1 = New MouseEventArgs(e.Button, e.Clicks, OFFSET, e.Y, e.Delta) MyBase.OnMouseDown(e1) Me.Select(hti.Row) End If Codes purpose is to select whole row istead of one cell. But I can't change my grid's columns width with mouse when my application is running, so what must I do? I sholud add some code to the IfElse-part in the code, but what? If there is anyone who can help me, I'd be very happy.

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