the version of your download jqgrid is newest?　My jqgrid version is 3.5.

        I also use beforeSubmit event to add some parameter to postdata. and as same as your code.

        But the difference is on the end  of the function must return something to jqgrid,let it know beforeSubmit function is ok.

the code

beforeSubmit: function(postdata, formid){
postdata.something = 'somevalue';
return return[true,''];
}

good luck.

According to the documentation:

http://www.trirand.com/jqgridw.....ditgridrow

this event is not applicable for your case. Moreover you should return a array whan you use the event.

I suggest you to use

onclickSubmit event or serializeEditData

Please look at the same place into the documentation

Regards

Tony

$('#myid').jqGrid('navGrid', '#pager',
		{edit: true, add: true, del: true}, 
        {
			beforeSubmit: function(postdata, formid){
				postdata.something = 'somevalue';
			} 
        });

But when I submit, I got this error :

Uncaught TypeError: Cannot read property '0' of undefined                                               jquery.jqGrid.min.js:222

Any idea ? Thanks 🙂