How to change the navbar after a user is logged in? - php

Question

I currently have 2 different navbars. One with Login and Sign up at the top and one with Account. I want the navbar to change to the one with Account after a user is logged in. My registration and login system is already working, so that won't have to change (connected to a database). Don't mind the names, it's for a school project.
These are my 2 navbars:
<div class="navbar">
<a class="active" href="Boomba.php">Boomba</a>
<div class="dropdown">
<button class="dropbtn">Boomba News
<i class="fa fa-caret-down"></i>
</button>
<div class="dropdown-content">
New News
Dead News
</div>
</div>
Boomba Store
Contact
<div class="floatr">
Sign Up
Login
Account
</div>
</div>
I currently have this at the top of the page:
<?php
session_start();
?>
Please let me know if there's an easier way overall to make this happen as well, this is my first website.
Thanks in advance :)
Edit:
My config file:
<?php
define('DB_SERVER', '-');
define('DB_USERNAME', '-');
define('DB_PASSWORD', '-');
define('DB_NAME', '-');
$link = mysqli_connect(DB_SERVER, DB_USERNAME, DB_PASSWORD, DB_NAME);
if($link === false){
die("ERROR: Could not connect. " . mysqli_connect_error());
}
?>
My Login file:
<?php
session_start();
if(isset($_SESSION["loggedin"]) && $_SESSION["loggedin"] === true){
header("location: welcome.php");
exit;
}
require_once "0config.php";
$username = $password = "";
$username_err = $password_err = "";
if($_SERVER["REQUEST_METHOD"] == "POST"){
if(empty(trim($_POST["username"]))){
$username_err = "Please enter username.";
} else{
$username = trim($_POST["username"]);
}
if(empty(trim($_POST["password"]))){
$password_err = "Please enter your password.";
} else{
$password = trim($_POST["password"]);
}
if(empty($username_err) && empty($password_err)){
$sql = "SELECT id, username, password FROM users WHERE username = ?";
if($stmt = mysqli_prepare($link, $sql)){
mysqli_stmt_bind_param($stmt, "s", $param_username);
$param_username = $username;
if(mysqli_stmt_execute($stmt)){
mysqli_stmt_store_result($stmt);
if(mysqli_stmt_num_rows($stmt) == 1){
mysqli_stmt_bind_result($stmt, $id, $username, $hashed_password);
if(mysqli_stmt_fetch($stmt)){
if(password_verify($password, $hashed_password)){
session_start();
$_SESSION["loggedin"] = true;
$_SESSION["id"] = $id;
$_SESSION["username"] = $username;
header("location: welcome.php");
} else{
$password_err = "The password you entered was not valid.";
}
}
} else{
$username_err = "No account found with that username.";
}
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
mysqli_stmt_close($stmt);
}
mysqli_close($link);
}
?>

Answer 1

You are duplicating a lot of code for your navbar here. You could do something like this if the other parts of your navbar don't need to change :
<div class="navbar">
<a class="active" href="Boomba.php">Boomba</a>
<div class="dropdown">
<button class="dropbtn">Boomba News
<i class="fa fa-caret-down"></i>
</button>
<div class="dropdown-content">
New News
Dead News
</div>
</div>
Boomba Store
Contact
<div class="floatr">
<?php if (isset($_SESSION['loggedin']) && $_SESSION['loggedin']): ?>
Account</li>
<?php else: ?>
Sign Up</li>
Login</li>
<?php endif; ?>
</div>
</div>

Answer 2

After the login operation, you must load the user-specific data to $_SESSION array. Imagine you have stored the user data to $_SESSION then you can check the $_SESSION value exist or not.
A sample code is given below. If you don't understand please let me know.
<?php
session_start();
if (isset($_SESSION["loggedin"]) && ($_SESSION["loggedin"] == TRUE)) {
//write a nav menu html code here
?>
<div>
nav-1
</div>
<?php
} else {
//write another nav menu html code here
?>
<div>
nav-2
</div>
<?php
}
?>