unconditionally selecting all rows in a DevExpress ASPxGridView

The select everything across all rows with no exceptions version of the JavaScript function here is here:

function DoSomethingInJavaScript(s, e) {
   if (Foo.GetVisibleRowsOnPage() == 0)
      return;
   if (!s.GetChecked())
      Foo.UnselectRows();
   else {
      Foo.SelectRows();
   }
}

 
 

I must confess that the "check all" checkbox behaves badly and does not always stay checked when it should. I did not have much time to work on this.