js记住用户名密码(摘抄)

CONTENT
    login.html
    welcome.html
    cookie.js
    common.js

login.html

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>login</title>
<script type="text/javascript" src="cookie.js"></script>
<script type="text/javascript" src="common.js"></script>
</head>
<body>
<form action="">
<p>
    <span>UserName:</span>
    <input id="userName" type="text" value=""/></p>
<p>
    <span>Password:</span>
    <input id="password" type="password" value=""/></p>
<p>
    <span style="font-size:12px; color:blue;">记住密码</span>
    <input id="saveCookie" type="checkbox" value="" /></p>
<p>
    <input id="submit" type="button" value="GO" />
</p>
</form>
</body>
</html>

welcome.html

cookie.js

//新建cookie。
//hours为空字符串时,cookie的生存期至浏览器会话结束。hours为数字0时,建立的是一个失效的cookie,这个cookie会覆盖已经建立过的同名、同path的cookie（如果这个cookie存在）。
function setCookie(name,value,hours,path){
    var name = escape(name);
    var value = escape(value);
    var expires = new Date();
     expires.setTime(expires.getTime() + hours*3600000);
     path = path == "" ? "" : ";path=" + path;
     _expires = (typeof hours) == "string" ? "" : ";expires=" + expires.toUTCString();
     document.cookie = name + "=" + value + _expires + path;
}
//获取cookie值
function getCookieValue(name){
    var name = escape(name);
    //读cookie属性，这将返回文档的所有cookie
    var allcookies = document.cookie;
    //查找名为name的cookie的开始位置
     name += "=";
    var pos = allcookies.indexOf(name);
    //如果找到了具有该名字的cookie，那么提取并使用它的值
    if (pos != -1){                                             //如果pos值为-1则说明搜索"version="失败
        var start = pos + name.length;                  //cookie值开始的位置
        var end = allcookies.indexOf(";",start);        //从cookie值开始的位置起搜索第一个";"的位置,即cookie值结尾的位置
        if (end == -1) end = allcookies.length;        //如果end值为-1说明cookie列表里只有一个cookie
        var value = allcookies.substring(start,end); //提取cookie的值
        return (value);                           //对它解码
         }
    else return "";                               //搜索失败，返回空字符串
}
//删除cookie
function deleteCookie(name,path){
    var name = escape(name);
    var expires = new Date(0);
     path = path == "" ? "" : ";path=" + path;
     document.cookie = name + "="+ ";expires=" + expires.toUTCString() + path;
}

common.js