怎样在DataGrid1_ItemCommand中弹出窗口?????

Question

怎样让
Sub DataGrid1_ItemCommand(sender As Object, e As DataGridCommandEventArgs)
    if e.commandname="sss" then   dim itemtype as listitemtype
   itemtype=e.item.itemtype
  if itemtype=listitemtype.item or itemtype=listitemtype.alternatingitem then    dim button as linkbutton
    button=ctype(e.Item.FindControl("linkbutton1"),linkbutton)
    '''''
    button.attributes.add("onclick","MM_openBrWindow('mrg.aspx','aaa','scrollbars=yes,width=400,height=250')")    end if
  end if
End Sub
弹出新的窗口?