login registration form in php code example

Example 1: how to make a working login system using code

<!DOCTYPE html>
<html>
<head>
	<title>Login</title>
	<script>
  firebase.initializeApp(firebaseConfig);
  const auth = firebase.auth();
  function signUp(){
    var email = document.getElementById("email");
    var password = document.getElementById("password");
    const promise = auth.createUserWithEmailAndPassword(email.value, password.value);
    promise.catch(e => alert(e.message));
    alert("Signed Up");
  }
  function signIn(){
    var email = document.getElementById("email");
    var password = document.getElementById("password");
    const promise = auth.signInWithEmailAndPassword(email.value, password.value);
    promise.catch(e => alert(e.message));
  }
  function signOut(){
    auth.signOut();
    alert("Signed Out");
  }

auth.onAuthStateChanged(function(user){
    if(user){
      var email = user.email;
      alert("Signed in as " + email);
      //Take user to a different or home page

      //is signed in
    }else{
      alert("No Active User");
      //no user is signed in
    }
  });g
	</script>
<style type="text/css">
	body{
	background-color: #55d6aa;
}
h1{
	background-color: #ff4d4d;
	margin: 10px auto;
	text-align: center;
	color: white;
}
#formContainer{
	background-color: white;
	box-shadow: 0 12px 16px 0 rgba(0,0,0,0.24), 0 17px 50px 0 rgba(0,0,0,0.19);

	width: 25%;
	height: 45;
	margin: 10px auto;
}
#header{
	width: 100%;
	height: 10px;
	background: black;
}
#email{
	width: 70%;
	height: 40px;
	display:block;
	margin: 25px auto;
	border: none;
	outline: none;
	border-bottom: 2px solid black;
}
#password{
	width: 70%;
	height: 40px;
	display: block;
	margin: 10px auto;
	border: none;
	outline: none;
	border-bottom: 2px solid black;
}
#signUp{
	background-color: #ff4d4d;
	color: white;
	border: none;
	font-weight: bold;
	padding: 15px 32px;
	border-radius: 10px;
	text-align: center;
	text-decoration: none;
	display: inline-block;
	font-size: 13px;
	margin-top: 20px;
	margin-left: 50px;
}
#signIn{
	background-color: #32ff7e;
	color: white;
	font-weight: bold;
	border: none;
	padding: 15px 35px;
	border-radius: 10px;
	text-align: center;
	text-decoration: none;
	font-size: 13px
}
#signOut{
	background-color: #FFA500;
	color: white;
	border: none;
	padding: 12px 32px;
	border-radius: 10px;
	text-align: center;
	text-decoration: none;
	display: inline-block;
	font-size: 13px;
	margin-top: 9px;
	margin-left: 74px;
	font-weight: bold;
}
button: hover{
box-shadow: 0 12px 16px 0 rgba(0,0,0,0.24), 0 7px 50px 0 rgba(0,0,0,0,.19);
}
</style>
</head>
<body>
	<h1>Login Here</h1>
	<div id="formContainer">
		<div id="header"> </div>
  <input type="email" placeholder="Email" id="email">
  <input type="password" placeholder="Password" id="password">

 <button onclick="signUp()" id="signUp"> Sign Up </button>
  <button onclick="signIn()" id="signIn"> Sign In </button>
  <button onclick="signOut()" id="signOut"> Sign Out </button>
Continue</a>
</body>
</html>

Example 2: php user login and registration

<?php
session_start();

// initializing variables
$username = "";
$email    = "";
$errors = array(); 

// connect to the database
$db = mysqli_connect('localhost', 'root', '', 'registration');

// REGISTER USER
if (isset($_POST['reg_user'])) {
  // receive all input values from the form
  $username = mysqli_real_escape_string($db, $_POST['username']);
  $email = mysqli_real_escape_string($db, $_POST['email']);
  $password_1 = mysqli_real_escape_string($db, $_POST['password_1']);
  $password_2 = mysqli_real_escape_string($db, $_POST['password_2']);

  // form validation: ensure that the form is correctly filled ...
  // by adding (array_push()) corresponding error unto $errors array
  if (empty($username)) { array_push($errors, "Username is required"); }
  if (empty($email)) { array_push($errors, "Email is required"); }
  if (empty($password_1)) { array_push($errors, "Password is required"); }
  if ($password_1 != $password_2) {
	array_push($errors, "The two passwords do not match");
  }

  // first check the database to make sure 
  // a user does not already exist with the same username and/or email
  $user_check_query = "SELECT * FROM users WHERE username='$username' OR email='$email' LIMIT 1";
  $result = mysqli_query($db, $user_check_query);
  $user = mysqli_fetch_assoc($result);
  
  if ($user) { // if user exists
    if ($user['username'] === $username) {
      array_push($errors, "Username already exists");
    }

    if ($user['email'] === $email) {
      array_push($errors, "email already exists");
    }
  }

  // Finally, register user if there are no errors in the form
  if (count($errors) == 0) {
  	$password = md5($password_1);//encrypt the password before saving in the database

  	$query = "INSERT INTO users (username, email, password) 
  			  VALUES('$username', '$email', '$password')";
  	mysqli_query($db, $query);
  	$_SESSION['username'] = $username;
  	$_SESSION['success'] = "You are now logged in";
  	header('location: index.php');
  }
}

// ...

Tags:

Misc Example