jQuery Grid Plugin - jqGrid

Hello

I'm trying cancel delete operation if it doesn't have correct value selected row column. But I can't achieve this with simple usage "return false";

I'm using beforeShowForm event for cancelling:

var deleteActionParameters = { modal: false, reloadAfterSubmit: true, mtype: "POST", delData: "", beforeShowForm: function(id) { return beforeSubmitDelete(id); }, onclickSubmit: function(eparams) { return { service: serviceName }; } };

and the method:

function beforeSubmitDelete(id) {

    var selectedRow = jQuery(dataGridId).getGridParam('selrow');

    var rowData = jQuery(dataGridId).getRowData(selectedRow);

    if ( (rowData.MyTextColumn != ""))

{

alert("You cant delete this row.... bla bla");

return false;

}

return true;

}

So, I want display alert message classic "you cant..." and later return the grid. Not displaying "Are you sure delete this row ?"...

Is there a way to achieve something like that ?

Thank.s