利用cookie实现用户自动登录的代码

时间：2015-01-23 来源：西部数据作者：西部数据

cookie 是由服务器发送到浏览器的变量,cookie 通常是服务器嵌入到用户计算机中的小文本文件,每当计算机通过浏览器请求一个页面,就会发送这个 cookie,实例代码如下:

<?php

echo( "Cookie created? : " . setcookie("cookie_name", "cookie_data" ) );

?>

<html>

<head>

<title>Cookie</title>

</head>

<body>

</body>

</html>

如果要删除 cookie只要设置cookie的过期时间就行了,实例代码如下:

<?php

setcookie ( "cookie_user", "test", time () + 60 * 60 * 24 * 30 );

setcookie ( "cookie_pass", md5 ( "test" ), time () + 60 * 60 * 24 * 30 );

function logout() {

setcookie ( "cookie_user", "", time () + 60 * 60 * 24 * 30 );

setcookie ( "cookie_pass", "", time () + 60 * 60 * 24 * 30 );

}

logout ();

echo $_COOKIE ['cookie_user'] . "<br />";

echo "You have successfully logged out.";

?>

我们在开发中经常会用到cookie自动登录,实例代码如下:

<?php

  $GLOBALS['username'] = "test";

  $GLOBALS['password'] = "test";



  function validatelogin ($username, $password){

    if (strcmp ($username, $GLOBALS['username']) == 0 && strcmp ($password, $GLOBALS['password']) == 0){

      setcookie ("cookie_user", $username, time()+60*60*24*30);

      setcookie ("cookie_pass", md5 ($password), time()+60*60*24*30);

      return true;

    } else {

      return false;

    }

  }

  if (validatelogin ("test","test")){

    echo "Successfully logged in.";

  } else {

    echo "Sorry, invalid login.";

  }

?>