Authentication with PHP and SQL

In this lesson, you will learn the basic concept of authentication with PHP.

Lesson Goals

To authenticate users with a login form.

Lesson Activities

A Database-less Login Form

A Database-less Login Form

Below is a simple login form that uses a hard-coded username and password.

Code Sample:

Authentication/Demos/SimpleLogin.php

<!DOCTYPE HTML>
<html>
<head>
<meta charset="UTF-8">
<title>Login Page</title>
</head>
<body>
<?php
	require 'Includes/Header.php';

	$msg='';
	$email = '';
	if (array_key_exists('LoggingIn',$_POST))
	{
		$email = $_POST['Email'];
		$pw = $_POST['Password'];
		if ($email == '[email protected]' && $pw == 'cowboy')
		{
			echo '<div align="center">Success</div>';
		}
		else
		{
			echo '<div align="center">Login Failed</div>';
			unset($_POST['LoggingIn']);
		}
	}

	if (!array_key_exists('LoggingIn',$_POST))
	{
?>

<div align="center">

	<h2>Log in</h2>
	<form method="post" action="SimpleLogin.php">
	<input type="hidden" name="LoggingIn" value="true">
		<table>
		<tr>
			<td>Email:</td>
			<td><input type="text" name="Email"
					value="<?php echo $email?>" size="25"></td>
		</tr>
		<tr>
			<td>Password:</td>
			<td>
			<input type="password" name="Password" size="10">
			</td>
		</tr>
		<tr>
			<td align="right" colspan="2">
			<input type="submit" value="Log in">
			</td>
		</tr>
		</table>
	</form>
</div>
<?php
	}
	require 'Includes/Footer.php';
?>
</body>
</html>

This page contains an HTML login form, which submits to itself (i.e, the action points to the same page). A hidden field, LoggingIn, is passed to the server when the user submits the form. The script checks to see if LoggingIn exists in the $_POST array. If it does, it processes the form input:

$email = $_POST['Email'];
$pw = $_POST['Password'];
if ($email == '[email protected]' && $pw == 'cowboy')
{
	echo '<div align="center">Success</div>';
}
else
{
	echo '<div align="center">Login Failed</div>';
	unset($_POST['LoggingIn']);
}

This code simply checks to see if the user's email and password match the hard-coded values ([email protected] and cowboy). If they do, it outputs a "success" message. If they don't, it outputs a "failed" message and removes LoggingIn from the $_POST array, so that the form will be displayed again.

Continue to the next lesson on Regular Expressions »

Authentication with PHP and SQL

Lesson Goals

Lesson Activities

A Database-less Login Form

Code Sample:

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