PHP Login System

Rate This Article

    Creating a login script for your site can make it look very professional. Our script is very simple and easy to implement. There are very few requirements in order to make it work, first is to have a PHP enabled server. Usually if your server is Linux based you can run PHP, check with your hosting company. Second you will need a database, for our example we will use a MySQL database, which again usually comes with a Linux based server. Our tutorial will track users with cookies.

Database

First we need to create the database to store users. Since this is a very simple login script we will only be using the username and password fields, but you can create as many as you wish. Below is the SQL statement you will need to run in your SQL query.

CREATE TABLE users (ID MEDIUMINT NOT NULL AUTO_INCREMENT PRIMARY KEY, username VARCHAR(60), password VARCHAR(60))

That statement creates a database table called users with 3 fields: password, username, and ID. The ID field is not used by you, but keeps a unique count within the database and can be used with a more advanced tutorial to pull information from the database easily.

Before we begin here is neat code that will allow you to run php in a .html or .htm page:
This goes in your .htaccess text file. If you do not know what that is ask you hosting provider.
AddHandler application/x-httpd-php52 .php .htm .html

Registration Page(added.php)

<?php
// Connects to your Database
mysql_connect("your.hostaddress.com", "username", "password") or die(mysql_error());
mysql_select_db("Database_Name") or die(mysql_error());

//This code runs if the form has been submitted
if (isset($_POST['submit'])) {

//This makes sure they did not leave any fields blank
if (!$_POST['username'] | !$_POST['pass'] | !$_POST['pass2'] ) {
die('You did not complete all of the required fields');
}

// checks if the username is in use
if (!get_magic_quotes_gpc()) {
$_POST['username'] = addslashes($_POST['username']);
}
$usercheck = $_POST['username'];
$check = mysql_query("SELECT username FROM users WHERE username = '$usercheck'")
or die(mysql_error());
$check2 = mysql_num_rows($check);

//if the name exists it gives an error
if ($check2 != 0) {
die('Sorry, the username '.$_POST['username'].' is already in use.');
}

// this makes sure both passwords entered match
if ($_POST['pass'] != $_POST['pass2']) {
die('Your passwords did not match. ');
}

// here we encrypt the password and add slashes if needed
$_POST['pass'] = md5($_POST['pass']);
if (!get_magic_quotes_gpc()) {
$_POST['pass'] = addslashes($_POST['pass']);
$_POST['username'] = addslashes($_POST['username']);
}

// now we insert it into the database
$insert = "INSERT INTO users (username, password)
VALUES ('".$_POST['username']."', '".$_POST['pass']."')";
$add_member = mysql_query($insert);
?>

<h1>Registered</h1>
<p>Thank you, you have registered - you may now login</a>.</p>

?php
}
else
{
?>

<form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="post">
<table border="0">
<tr><td>Username:</td><td>
<input type="text" name="username" maxlength="60">
</td></tr>
<tr><td>Password:</td><td>
<input type="password" name="pass" maxlength="10">
</td></tr>
<tr><td>Confirm Password:</td><td>
<input type="password" name="pass2" maxlength="10">
</td></tr>
<tr><th colspan=2><input type="submit" name="submit" value="Register"></th></tr> </table>
</form>

<?php
}
?>

The code above first checks to see if a form was submitted, if so it checks to make sure all data is valid (passwords are the same, and username is not already taken). If everything checks out it adds the user to the database, if not then it displays the appropriate error.

If the form has not been submitted, they only see a blank form ready to be filled with information.

Continued on Part 2