重定向到登录前的页面

Question

I have a page where if you are logged in, you see your username and avatar. If you are not logged in, then you see a connect button that will redirect you to another page where you can enter your username and your password to log in.
What I want to do is after you log in and are redirected on the page you were before logging in.

 <?php
session_start();

if (isset($_POST["logIn"])) 
{
              .....

header("Location:../index.php");
 } else
 {  ...}

What should I change to header?

Answer 1

1- on login page, you need to get referrer url (from where it was redirected to login page that user not logged in)

2- In that login form, make hidden field with that referrer value like:

<input type="hidden" name="redirect" value="<?php echo $_SERVER['HTTP_REFERER'];?>">

3- On submit, and verified username and password from database, redirect to this URL like

header('location: '.$_POST['redirect']);