这是我连接数据库的类,它有一个循环查看结果的查询方法,但它给了我这个错误:
致命错误:第30行的C:\ Apache24 \ htdocs \ classes \ DB.php中的Call to undefined method mysqli::fetch_assoc()
我知道问题出在我的query()方法中,我尝试使用非静态属性,但错误仍在继续。
<?php
class DB {
private static $db_name = "data_db";
private static $db_user = "root";
private static $db_pass = "root";
private static $db_host = "localhost";
private static $row;
private static $instance = null;
public static function get_instance() {
if(!isset(self::$instance))
self::$instance = new self;
return self::$instance;
}
//returns mysqli object.
private function __construct() {
$this->mysqli = new mysqli(self::$db_host, self::$db_user, self::$db_pass, self::$db_name);
}
public function __destruct() {
$this->mysqli->close();
}
public function query($query) {
if ($result = $this->mysqli->query($query)) {
if($result->num_rows > 1) {
$rows = array();
while ($item = $result->fetch_assoc()) {
$rows[] = $item;
}
} else {
$rows = $result->fetch_assoc();
}
return $rows;
}
}
/**
* Private clone method to prevent cloning of the instance of the
* *Singleton* instance.
*
* @return void
*/
private function __clone() {}
/**
* Private unserialize method to prevent unserializing of the *Singleton*
* instance.
*
* @return void
*/
private function __wakeup() {}
}
?>
答案 0 :(得分:2)
MySQLi对象没有方法fetch_assoc。您必须使用查询结果。例如:
public function query($query) {
$result = $this->mysqli->query($query);
$rows = array();
while ($item = $result->fetch_assoc()) {
$rows[] = $item;
}
return $items;
}