jquery input checkbox checked unchecked function code example
Example 1: jquery set checkbox checked unchecked
//jQuery 1.6+ use
$('.checkbox').prop('checked', true); //false for uncheck
//jQuery 1.5.x and below use
$('.checkbox').attr('checked', true); //false for uncheck
Example 2: check a checkbox jquery
$('#grepperRocks').prop('checked', true);