JS checkout全选以及反选

   function allCheck(name, boolValue) {
        var allvalue = document.getElementsByName(name);
        for (var i = 0; i < allvalue.length; i++) {
            if (allvalue[i].type == "checkbox")
                allvalue[i].checked = boolValue;
        }
    }

    //反选 参数为复选框名称
    function reserveCheck(name) {
        var revalue = document.getElementsByName(name);
        for (i = 0; i < revalue.length; i++) {
            if (revalue[i].checked == true)
                revalue[i].checked = false;
            else
                revalue[i].checked = true;
        }
    }

    $("#select_all_tasks").click(function () {
        if ($("#select_all_tasks").attr("checked")) {
            allCheck('choice', true)
        } else {
            allCheck('choice', false)
        }
    })