Select and Dselect

selectall.js

$(function(){

	// add multiple select / deselect functionality
	$("#selectall").click(function () {
		  $('.case').attr('checked', this.checked);
	});

	// if all checkbox are selected, check the selectall checkbox
	// and viceversa
	$(".case").click(function(){

		if($(".case").length == $(".case:checked").length) {
			$("#selectall").attr("checked", "checked");
		} else {
			$("#selectall").removeAttr("checked");
		}

	});
});