javascript 设置cookie和取得cookie

代吗实例：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>cookie</title>
    <script>
        function  setCookie(name,value,expires,path,domain,secure)  {
            var cookieName=encodeURIComponent(name)+'='+encodeURIComponent(value);
            if(expires instanceof Date ) {
                cookieName+=';expires='+expires;
            }
            if(path) {
                cookieName+=';path='+path;
            }
            if(domain) {domain
                cookieName+=';domain='+domain;
            }
            if(secure) {
                cookieName+=';secure';
            }
            document.cookie=cookieName;
        }
        function  getCookie(name) {
            var cookieName=encodeURIComponent(name)+'=';
            var cookieStart = document.cookie.indexOf(cookieName);

            if (cookieStart>-1) {
                var cookieEnd=document.cookie.indexOf(';',cookieStart);
                if(cookieEnd==-1){
                    cookieEnd=documet.cookie.length;
                }
                cookieValue=decodeURIComponent(document.cookie.substring(cookieStart+cookieName.length,cookieEnd));
                return   cookieValue;
            }
        }
        alert(getCookie('user'));
        alert(getCookie('email'));
        alert(getCookie('url'));
        function setCookieDate(day) {            //传递一个天数，比如传递7，就7天后失效
            var date = null;
            if (typeof day == 'number' && day > 0) {
                date = new Date();
                date.setDate(date.getDate() + day);
            } else {
                throw new Error('您传递的天数不合法！必须是数字且大于0');
            }
            return date;
        }
</script>
</head>
<p>设置cookie和取得cookie </p>
</body>
</html>