ini halaman user.php

<?php

function register_user($nama, $pass){
    global $link;

    // mencegah injection
    $nama = mysqli_real_escape_string($link, $_POST['username']);
    $pass = mysqli_real_escape_string($link, $_POST['password']);

    $pass = password_hash($pass, PASSWORD_DEFAULT);
    // $pass = md5($pass);
    $query ="INSERT INTO users (username, password) VALUES ('$nama','$pass')";

    if(mysqli_query($link,$query)){
        return true;
    }else{
        return false;
    }
}

// menguji nama kembar

function register_cek_nama($nama){
    global $link;
    $nama = mysqli_real_escape_string($link, $nama);

    $query = "SELECT * FROM users WHERE username = '$nama' ";

    if( $result = mysqli_query($link, $query)){
        if(mysqli_num_rows($result) == 0) return true;
        else return false;
    }
}

// menguji nama di database

function login_cek_nama($nama){
    global $link;
    $nama = mysqli_real_escape_string($link, $_POST['username']);

    $query = "SELECT * FROM users WHERE username = '$nama' ";

    if( $result = mysqli_query($link, $query)){
        if(mysqli_num_rows($result) == 0) return true;
        else return false;
    }
}

// untuk login
function cek_data($nama, $pass){
    global $link;

    // mencegah sql injection
    $nama = mysqli_real_escape_string($link, $nama);
    $pass = mysqli_real_escape_string($link, $pass);

    $query = "SELECT password FROM users WHERE  username = '$nama'";
    $result = mysqli_query($link, $query);
    $hash = mysqli_fetch_assoc($result)['password'];


    if( password_verify($pass, $hash)){
        return true;
    }else{
        return false;
    }
}

?>