调用未定义的方法mysqli :: result（）

Question

你能帮我们找出错误吗，谢谢你的帮助。

  

调用未定义的方法mysqli :: result（）

<?php

    function user_exists($username) {
        $db = mysqli_connect("localhost","root","","sample");
        $query = $db->query("SELECT COUNT(`id`) FROM `users` WHERE username = '$username'");
        return ($db->result($query, 0) == 1) ? true : false;
    }

 ?>

Answer 1

尝试这样：

    function user_exists($username) {
        $db = mysqli_connect("localhost","root","","sample");
        $result = $db->query("SELECT `id` FROM `users` WHERE username = '$username'");
        return ($result->num_rows ? true : false);}