jQuery Grid Plugin - jqGrid

$(document).ready(function () {
         $.ajax({
             url: 'sheet.aspx?q=load',
             datatype: 'json',
             success: function (data) {
                 $("#grid_id").jqGrid({
                     url: '',
                     datatype: 'clientSide',
                     mtype: 'POST',
                     height: 'auto',
                     colNames: data.colNames, //get from code behide
                     colModel: data.colModel, //get from code behide
                     viewrecords: true,
                     rowNum: 15,
                     headtitles: true,
                     data: data.rows,
                     jsonReader: {
                         root: "rows"
                     },
                     hidegrid: false,
                     cellurl: 'sheet.aspx?q=update',
                     beforeSubmitCell: function (rowid, celname, value, iRow, iCol) {
                         return { celname: celname }
                     },
                     loadError: function (xhr, status, error) { alert(status + " " + error); }
                 });

                 jQuery(".jqgrow td input").each(function () {  //detect all input
                     jQuery(this).click(function () {
                         jQuery(this).change(function () {
                             var data = new Array(3);
                             data[0] = "{id:\"" + $(this).parents('tr').attr('id').replace(/^\s*|\s*$/g, "") + "\","; // replace = trim
                             var colname = $(this).parents('td').attr('aria-describedby').replace("grid_id_", ""); // get colname
                             var value = ($(this).prop('checked')) ? "True" : "False";
                             data[1] = colname + ":\"" + value + "\",";
                             data[2] = "celname:\"" + colname + "\"}"
                             $.ajax({
                                 url: 'sheet.aspx?q=update',
                                 type: 'POST',
                                 data: eval('(' + data[0] + data[1] + data[2] + ')'),  //eval is string to json
                                 beforeSend: function (jqXHR, textStatus) { jQuery('#grid_id').block({ message: '<h1>Loading...</h1>' }); },
                                 complete: function (jqXHR, textStatus) { jQuery('#grid_id').unblock(); },
                                 loadError: function (xhr, status, error) { alert(status + " " + error); }
                             });
                         });
                     });
                 });
             },
             error: function (x, e) {
                 alert(x.readyState + " " + x.status + " " + e.msg);
             }
         });
     });

colmodel: "{"name":"test","width":40,"align":"center","editoptions":{"value":"True:False"},"edittype":"checkbox","formatter":"checkbox","formatoptions":{"disabled":false}},"