9.4 使用 cookie 作为计数器

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <script>
        window.onload = initPage;
        function initPage() {
            var expireDate = new Date();
            expireDate.setMonth(expireDate.getMonth() + 6);
            var hitCt = parseInt(cookieVal("pageHit"));
            hitCt++;
            document.cookie = "pageHit=" + hitCt + ";expires=" + expireDate.toGMTString();

            console.log(document.cookie);
        }

        function cookieVal(cookieName) {
            var thisCookie = document.cookie.split("; ");
            for (var i=0; i<thisCookie.length; i++) {
                if (cookieName == thisCookie[i].split("=")[0]) {
                    return thisCookie[i].split("=")[1]; }
            }
            return 0;
        }
    </script>
</head>
<body>
<p>JavaScript</p>
</form>
</body>
</html>