兩種方式：1、使用“setcookie(cookiename,NULL)”語句將cookie的值設置為空；2、使用“setcookie('cookiename','',time()-3600)”語句將cookie的過期時間設置為過去。

本教程操作環境：windows7系統、PHP7.1版，DELL G3電腦

php刪除/清除cookie的兩種方法

將cookie的值設置為空,即：setcookie('cookiename', '')或者setcookie(cookiename, NULL);

將cookie的過期時間設置為過去，即：setcookie('cookiename','',time()-3600);

方法一：將cookie的值設置為空

<?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 ); } /* http://www.manongjc.com/article/1253.html */ logout (); echo $_COOKIE ['cookie_user'] . "<br />"; echo "You have successfully logged out."; ?>

方法二：將cookie的過期時間設置為過去

<?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", "test", time () - 100 );   setcookie ( "cookie_pass", md5 ( "test" ), time () - 100 ); } logout (); echo $_COOKIE ['cookie_user'] . "<br />"; echo "You have successfully logged out."; ?>

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