$.ajax({
         url: "<?php echo Router::url(array('controller'=>'home','action'=>'checkAssignList'));?>",
         type: 'POST',
         data: { userid : userid  },           
          success: function(data){   
             if (data == '0') {
                string += "<tr><td colspan=\"2\" ><center> No data </center> </td></tr>";
             } else {
                catlist = $.parseJSON(data);
                $.each(catlist, function(index, val) {
                  string+="<tr id='row"+val.Category.id+"'>";
                  string+="<td>"+val.Category.name+"</td> ";
                  string+="<td><button  onclick=\"unAssign('"+val.Category.id+"', '"+ userid+"')\" class='btn btn-small btn_unAssignt12'>unAssign</button></td> ";
                  string+="</tr>";
                });
             }
             $('#categoriesDatalist').html(string);
          }//end success !
       })//end ajax function loadalllistUsersAssign