register_stmt_process.php

<?php

	include 'includes/dbconnection.php';

	if(isset($_POST['submitBtn'])) {

		$name = mysqli_real_escape_string($conn, $_POST['inputName']);
		$email = mysqli_real_escape_string($conn, $_POST['inputEmail']);
		$username = mysqli_real_escape_string($conn, $_POST['inputUsername']);
		$password = mysqli_real_escape_string($conn, $_POST['inputPassword']);

		$sql = "INSERT INTO users(name, email, username, password) VALUES (?, ?, ?, ?)";

		$stmt = mysqli_stmt_init($conn);

		if(!mysqli_stmt_prepare($stmt, $sql)) {
			echo 'SQL Error!';
		} else {
			mysqli_stmt_bind_param($stmt, 'ssss', $name, $email, $username, $password);

			mysqli_stmt_execute($stmt);
		}

		mysqli_query($conn, $sql);

		header('Location: register.php?result=success');

	} else {
		header('Location: register.php');
	}