For Each oRow As GridViewRowInfo In Me.RadGridView1.MasterView.Rows
'get existing item number value
Dim strItemNumber As String = oRow.Cells("vchrItemNumberGP").Value
Dim intMasterOrderItemFK As Int32 = oRow.Cells("intMasterOrderItemFK").Value
'if an existing item number value is found that is equal to the new value, then msgbox warning and exit sub
If intMasterOrderItemFK = Me.RadGridView1.MasterView.TableAddNewRow.Cells("intMasterOrderItemFK").Value Then
MsgBox("Item already exists in this Suborder.")
Me.RadGridView1.CancelEdit()
Me.RadGridView1.MasterView.TableAddNewRow.CancelAddNewRow()
Exit Sub
End If
Next