check all/ unchech akk

by Akram kamal

HTML

<table id="tab1"><tr><td>
    <input type="checkbox" name="checkAll" id="checkAll">全選
    <input type="checkbox" name="book" id="book" value="book1">book1
    <input type="checkbox" name="book" id="book" value="book2">book2
    <input type="checkbox" name="book" id="book" value="book3">book3
    <input type="checkbox" name="book" id="book" value="book4">book4
        <input type="checkbox" name="book" id="book" value="book5">book5</td></tr></table>

JavaScript

$("#tab1 #checkAll").click(function () {
        if ($("#tab1 #checkAll").is(':checked')) {
            $("#tab1 input[type=checkbox]").each(function () {
                $(this).prop("checked", true);
            });

        } else {
            $("#tab1 input[type=checkbox]").each(function () {
                $(this).prop("checked", false);
            });
        }
    });