Uncheck the checkbox using jquery

Uncheck the checkbox using jquery

I've an Textbox in which the autocomplete is enabled using jquery ajax.if i select one value means it have to check the corresponding checkbox.This one works me properly.If i delete that value means it have to uncheck that checkbox..Help me out please..My Jquery code is 
  2. $('#prgrp').on('keydown', function (evt)
  3.              {
  4.                  var txt = $("#prgrp").val();
  5.                  var valueArray = txt.split(';');
  6.                  var valueSortArray = valueArray.sort();
  7.                  for (var i = 0; i < parseInt( txt.split(';').length); i++)
  8.                  {
  9.                         $('#<%= group12.ClientID%> input').each(function () {
  10.                          if ($(this).val() == valueSortArray[i].valueOf())
  11.                          {
  12.                              $(this).attr('checked', true);
  13.                          }
  14.                       });
  15.                  }
  16. });
  • Here prgrp is Textbox id and group12 is checkboxlist id which is bind from database using Asp.net C#
  • i deleted that value 0042A but the checkbox is still checked..This is my problem help me out please