登录页面上的会话重定向循环解决方法

Question

I am looking to placing all code above in header.php which I include.

The first few lines of header has :

<?php session_start();
if(!isset($_SESSION["loggedin"])){
header("Location: login.php");
exit;}
?>

The unfortunate consequence of this is that when the user gets redirected to login.php they hit a redirect loop.

Would the best way forward to be creating an If statement along the lines of pseudo:

if (page="login.php")
{
  //do not redirect to login.php
}

Before the session_start();?

Answer 1

You can wrap the code

if(!isset($_SESSION["loggedin"])){
header("Location: login.php");
exit;}

In a function such as:

function ensureLoggedIn()
{
  if (!isset($_SESSION["loggedin"]))
  {
    header("Location: login.php");
    exit;
  }
}

Then you call this function from all the pages where authentication is required.

Such as calling this function on secretpage.php will redirect to login.php if the user is not logged in.

Login.php should not have this function.