<?php
error_reporting(0);
$path = ‘./tmp/‘;
$sess_name = session_name();
echo $sess_name;
$sess_id = $_GET[$sess_name];
echo $sess_id;
session_id($sess_id);
session_save_path($path);
session_start();
if ((trim($_POST[‘username‘])) != ‘tm‘ and (trim($_POST[‘password‘]) != ‘111‘))
{
	echo "<script>alert(‘用戶名與密碼錯誤！‘);location.href=‘index.php‘</script>";
}
$_SESSION[‘admin‘] = ‘mrsoft‘;
?>

　　即便執行到以上的alert語句。但在location跳轉之前仍然會執行後面的session屬性賦值語句。

PHP執行Session與前端JS之間的關系