我在我的代碼中遇到了這個(gè)問題，我想在 _cart-templet.php 文件中計(jì)算我的小計(jì)部分的價(jià)格，但它給了我錯(cuò)誤，我在下面包含了這個(gè)錯(cuò)誤的所有必要代碼：致命錯(cuò)誤：未捕獲錯(cuò)誤：調(diào)用 C:\xampp\htdocs\MobileShopee\Mobile Shopee\Templet_cart-templet.php:78 中數(shù)組的成員函數(shù) getSum() 堆棧跟蹤：#0 C:\xampp\htdocs\MobileShopee\ Mobile Shopee\cart.php(10): include() #1 {main} throw in C:\xampp\htdocs\MobileShopee\Mobile Shopee\Templet_cart-templet.php on line 78"主 cart.php 文件：<?phpob_start();//include header.phpinclude ('header.php');?>    <?php    //include products.php    include ('Templet/_cart-templet.php');    //include top-sale.php    include ('Templet/_new-phones.php');    ?><?php//include footer.phpinclude ('footer.php');?>這是我的 Cart.php 文件： public function getSum($arr){        if(isset($arr)){            $sum = 0;            foreach ($arr as $item){                $sum += floatval($item[0]);            }            return sprintf('%.2f' , $sum);        }    }這是我的 functions.php 文件：<?php//require MYSQL Connectionrequire ("database/DBController.php");//require product classrequire ("database/Product.php");//require product classrequire ("database/Blog.php");//require cart classrequire ("database/Cart.php");//DB Controller$db = new DBController();//product object$product = new Product($db);$product_shuffle = $product->getData();//blog object$blog = new Blog($db);//cart object$cart = new Cart($db);