如何在 PHP 中调试 "Call to a member function X on null"?

How to debug "Call to a member function X on null" in PHP?

我被 php CMS 中的错误卡住了:

PHP Fatal error: Call to a member function send_sms() on null in /home/zleepcom/public_html/view/CartView.php on line 117

这是调用方法的代码:

  $this->notify->sms_send($order->phone,'Ваш заказ №'.$order->id.' принят. На сумму '.$order->total_price.' '.$this->currency->sign.'. Спасибо за заказ!');

这是函数:

    public function send_sms($r,$m)
{

public $sender='xxx';
public $slogin='xxx';
public $spwd='xxx';    
public $pdo;
    try{
        $pdo = new PDO ("mysql:host=77.120.116.10;dbname=users",$slogin,$spwd);
        $pdo->query("SET NAMES utf8;");

        $pdo->query("INSERT INTO `{$slogin}` (`number`,`message`,`sign`) VALUES ('$r','$m','$sender')");

    }catch(Exception $e){
            $client = new SoapClient ('http://turbosms.in.ua/api/wsdl.html'); 
            $auth = array( 
                'login' => $slogin, 
                'password' => $spwd 
            ); 
            $res=$client->Auth($auth);
            $sms = array( 
                'sender' => $sender, 
                'destination' => $r, 
                'text' => $m
            );
            $res=$client->SendSMS($sms); 
    }
  }

如有任何帮助,我将不胜感激

错误的意思是$this->notifynull。您发布的内容还不足以让我们说 为什么 它是 null(它必须在您之前的代码中),但这是您的问题。