1，用javascript脚本来保存访问者的cookie值，当用户下次登录时，直接读取保存在硬盘上的cookie值，以验证是否登录。
代码：
<!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" xml:lang="en" lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>JavaScript Cookie-www.jb200.com</title>
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
function register(name)
{
var curdate = new Date();
curdate.setMonth(curdate.getMonth() + 9);
cookieExpires = curdate.toUTCString();
final_cookie = "mycookie=" + encodeURIComponent(name) + ";expires_on = " + cookieExpires;
document.cookie = final_cookie;
}
function getCookie(cookie_name)
{
var search_cookie = cookie_name + "="
if (document.cookie.length > 0)
{
start_position = document.cookie.indexOf(search_cookie)
if (start_position!= -1)
{
start_position += search_cookie.length
end_position = document.cookie.indexOf(";", start_position)
if (end_position == -1)
end_position = document.cookie.length
return (decodeURIComponent(document.cookie.substring(start_position, end_position)))
}
}
}
//]]>
</script>
</head>
<body>
<h1 style="color: red">JavaScript Cookie</h1>
<hr />
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
var username = getCookie("mycookie")
if (username)
{
document.write("Welcome Back, ", username)
}
if (username == null)
{
document.write("You haven't been here in the last nine months...")
document.write("When you return to this page in next nine months, ");
document.write("your name will be displayed...with Welcome.");
document.write('<form onsubmit = "return false">');
document.write('<p>Enter your name: </p>');
document.write('<input type="text" name="username" size="40">');
document.write('<input type = "button" value= "Register"');
document.write('onClick="register(this.form.username.value); history.go(0)">');
document.write('</form>');
}
//]]>
</script>
</body>
</html>
2，以下脚本删除保存在硬盘上的cookie数据。
代码：
<!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" xml:lang="en" lang="en">
<head><br>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>JavaScript Cookie 的例子-删除cookie--www.jb200.com</title>
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
function register(name)
{
var nowDate = new Date();
nowDate.setMonth(nowDate.getMonth() + 9);
cookieExpires = nowDate.toUTCString();
final_cookie = "mycookie=" + encodeURIComponent(name) + ";expires_on = " + cookieExpires;
document.cookie = final_cookie;
}
function getCookie(cookie_name)
{
var search_cookie = cookie_name + "="
if (document.cookie.length > 0)
{
start_position = document.cookie.indexOf(search_cookie)
if (start_position!= -1)
{
start_position += search_cookie.length
end_position = document.cookie.indexOf(";", start_position)
if (end_position == -1)
end_position = document.cookie.length
return (decodeURIComponent(document.cookie.substring(start_position, end_position)))
}
}
}
//]]>
</script>
</head>
<body>
<h1 style="color: red">JavaScript Cookie - 例子</h1>
<hr />
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
var yourname = getCookie("mycookie")
if (yourname)
{
document.write("Welcome Back, ", yourname)
}
if (yourname == null)
{
document.write("You haven't been here in the last nine months...")
document.write("When you return to this page in next nine months, ");
document.write("your name will be displayed...with Welcome.");
document.write('<form onsubmit = "return false">');
document.write('<p>Enter your name: </p>');
document.write('<input type="text" name="username" size="40">');
document.write('<input type = "button" value= "Register"');
document.write('onClick="register(this.form.username.value); history.go(0)">');
document.write('</form>');
}
//]]>
</script>
</body>
</html>