注册时使用mysql_query（）时返回不正确

Question

I am very beginner in PHP.

When I am registering a new user, I received an unproper 'return' (-1 instead of 1) when I am using mysql_query. Without line with "mysql_query" return is proper.

What am I doing wrong?

public function register ($username, $password, $activationcode) {
    $username = $this->parse($username);
    $password = $this->parse($password);

    $query_search = "SELECT * from tbl_user WHERE username = '".$username."' ";
    $query_exec = mysql_query($query_search) or die(mysql_error());
    $no_of_rows = mysql_num_rows($query_exec);

if ($no_of_rows == 0)
{
        $newUser="INSERT INTO tbl_user(username, password,activationcode) VALUES ('".$username."', '".$password. "','".$activationcode."')"; 
        if(mysql_query($newUser))
        {
        return 1;
        }
}else {
    return -1;
    }
}

Answer 1

Let me say I would not code it that way, but here is what I would do to correct your code while keeping your structure:

include($_SERVER['DOCUMENT_ROOT']."/database.php"); // your database connection values that are into a $database variable that we will use now. For example, mysqli_connect(DB_SERVER, DB_USER, DB_PASSWORD);

public function register ($username, $password, $activationcode){
    $username = $this->parse($username);
    $password = $this->parse($password);

    mysqli_select_db(DB_NAME); // the name of the database you will use.

    $sql = mysqli_query($database, "SELECT * from tbl_user WHERE username = '$username'") or die(mysqli_error());

    if(mysqli_num_rows($sql) == 0){
        $newUser = "INSERT INTO tbl_user (username, password, activationcode) VALUES ('$username', '$password', '$activationcode')";
        if(mysqli_query($database, $newUser)){
            return 1;
        } else {
            return -1; // you might get a problem in here too.
        }
    } else {
        return -1;
    }
}