Application Error occur when touch move on datagridview

Hi,

Touch move on datagridview without problem on IE and Chrome but iPad Safari show “Application Error” alert box, Wisej version is 1.4.65.0, using Dot Net 4.5 with Visual Stuidio 2015, follow code for your reference, thanks a lot.

—————————————————————————————————–

Private myCurrAutoSTouchMove As Point

Private Sub DataGridViewDocDetail_TouchStart(sender As Object, e As TouchEventArgs) Handles DataGridViewDocDetail.TouchStart
myCurrAutoSTouchMove = DataGridViewDocDetail.AutoScrollPosition
End Sub

Private Sub DataGridViewDocDetail_TouchMove(sender As Object, e As TouchEventArgs) Handles DataGridViewDocDetail.TouchMove
If e.Locations.Count > 1 Then
Dim mCurrAutoS As Point
Dim mDeslocation As Point = e.Locations(1) – e.Locations(0)
mCurrAutoS.X = Math.Abs(myCurrAutoSTouchMove.X) + mDeslocation.X
mCurrAutoS.Y = Math.Abs(myCurrAutoSTouchMove.Y) + mDeslocation.Y

DataGridViewDocDetail.AutoScrollPosition = mCurrAutoS
End If
End Sub