Day 19 - Members Area - Become PHP Expert in 30 days

[admin]

Members Area

Members Area is pages in an application that are only available for logged in users.

On Day 18, we created login page (login.php). If login was successful, we just show a message.

echo "Password Matched"; 

Instead of showing the message, we need user redirected to another page.

Redirect User To Another Page

In PHP, you can redirect a user to another page using code

header("Location: URL_HERE"); 

Lets Test

hostonnet.php

<?php

header("Location: http://hostonnet.com");

Upload the file to your web site. On visiting the file, you will get redirected to URL specified in the code, in our case http://hostonnet.com


Create Members Only Page

Now we know how to redirect user to another page/URL.

Lets create our Members only page, so we can redirect users to this page after successful login.

tasks.php

<?php

echo "<h1>Welcome to members only page. This page is under construction.</h1>";

Since our application is TODO task manager, we named our members page tasks.php

Edit login.php and redirect user to tasks.php

Open login.php

Find

if ($userInfo['password'] == $password) {
    echo "Password Matched";
} 

Replace with

if ($userInfo['password'] == $password) {
    header("Location: tasks.php");
    exit;
} 

Check if User Logged In

Currently our tasks.php is simple PHP page. It do nothing other than printing some text.

What we need to do is make sure only logged in members can see this page.

How we know if user is logged in ? We can set a COOKIE or SESSION.

When user login, we set a SESSION variable. On tasks.php page, we check if SESSION is set, if not redirect user to login page.

So lets edit login.php again

login.php

Find

if ($userInfo['password'] == $password) {
    header("Location: tasks.php");
    exit;
} 

Replace With

if ($userInfo['password'] == $password) {
    session_start();
    $_SESSION['AUTH_USER'] = $userInfo;
    header("Location: tasks.php");
    exit;
} 

tasks.php

Use following code for tasks.php

<?php

session_start();

if (!isset($_SESSION['AUTH_USER'])) {
    echo "User is not logged in<br>";
    echo "<a href=login.html>click here</a> to go to login page";
    exit;
}

echo "<h1>Welcome to members only page. This page is under construction.</h1>";

We check if SESSION is set. If no session set, we show error message and exit program.

Logging Off User

Logging off user is simple. Just destroy the session.

logout.php

<?php

session_start();
session_destroy();

echo "<p>User logged off successfully.</p>";

Now lets add a log out link from our tasks page.

Open tasks.php

Add

echo "<p><a href='logout.php'>Click here to logout</a>"; 

to end of the file.