<asp:DataGrid .. OnItemDataBound="DataGrid_DataBound"..>
..
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Sub ItemDataBound(Sender As Object, e As DataGridItemEventArgs)
If e.Item.ItemIndex <> -1 Then
e.Item.Attributes("onMouseOver") = "javascript:this.bgColor='#E0E0E0';"
e.Item.Attributes("onMouseOut") = "javascript:this.bgColor='#FFFFFF';"
End If
End Sub