How to keep me logged in on a php form - php

Question

I created a login page to a php form that I also created. Whenever I fill the form with the required fields, I get redirected to a 'Thank you for your submission' page, that has the link 'Go Back to Form'.
The problem is, when I press the 'Go Back to Form' link, it assumes that I am not logged in anymore, and so I get directed to a white page instead.
Login Page Code:
<?php session_start(); ?>
<?php
if (isset($_POST['submitlogin'])) {
$username1= $_POST['username'];
$pass1= $_POST['password'];
if($username1==$nomepass && $pass1==$passpass) {
$_SESSION['CurrentUser']= $username1;
echo '**HTML FORM**';
}
else
{
//...
}
}
?>
Form 'Thank you' Page:
HTML code Inside PHP echo
...
echo ' <p> Back to login page </p>' ;

Answer 1

On the login form and subsequent pages using sessions, put an if statement to check if the session that tells that a person has logged in is set. Then, it will redirect you to a home page or whatever page you want if you are logged in.
That way, if you are not logged in, you can login otherwise, it will redirect you
<?php
session_start();
if(isset($_SESSION['CurrentUser'])){
// redirect to some page
}
else{
// do something else
}
You could also make that line to read as:
if(isset($_SESSION['CurrentUser']) && !empty($_SESSION['CurrentUser']))

Answer 2

Normally we can use the session and call it on every page where I wan to allow the register user, for example..
This is you php code
if (isset($_POST['submitlogin'])) {
$username1= $_POST['username'];
$pass1= $_POST['password'];
if($username1==$nomepass && $pass1==$passpass) {
$_SESSION['CurrentUser']= $username1;
header('location:index.php');
}
Now you can code in the index page like this...
<?php
if(!isset($_SESSION['currentUser']))
{
header('location:signin.php');
}
?>
if the session is set tyhen the above code will keep you login otherwise you will redirect to signin page..