这个问题在这里已经有答案了：

mysql\u fetch\u array（）/mysql\u fetch\u assoc（）/mysql\u fetch\u row（）/mysql\u num\u rows等…期望参数1是资源（31个答案）
两年前关门了。
我出错了
代码如下：

<?php

//db connection

$dbserv="localhost:3306";
$dbuser="root";
$dbpass="firepower";
$dbname="account_data";
$db_connect=new mysqli($dbserv, $dbuser, $dbpass, $dbname);

if($db_connect->connect_errno){
    die("Error trying to connect to database");
}

session_start();

if(isset($_SESSION['current_page'])){
  $prev_page=$_SESSION['current_page'];
  $_SESSION['current_page'] = basename($_SERVER['PHP_SELF']);
}
else{
  $prev_page='';
}

if(!isset($_SESSION['email'])){
  header('location:'.'index.php?_rdr');
  die();
}

$limit=$_SESSION['limit'];
$index=1;
$first=true;
$products_ordered='';

while($index<=$limit){
  if(isset($_POST[$index]) && $first==true){
    $products_ordered.=$_POST[$index].' x Pizza '.$_SESSION['prod_name'][$index];
    $first=false;
  }
  else if(isset($_POST[$index]) && $first==false){
    $products_ordered.=', '.$_POST[$index].' x Pizza '.$_SESSION['prod_name'][$index];
  }
  $index++;
}

//insert order into db

$user_email=$_SESSION['email'];
$total_price=$_SESSION['order_price'];

$query="INSERT INTO orders (email, products_ordered, total_price) VALUES (?, ?, ?)";
$sql_sec=$db_connect->prepare($query);
$sql_sec->bind_param("ssi", $user_email, $products_ordered, $total_price);
$sql_sec->execute();
$result=$sql_sec->get_result();

if(mysqli_num_rows($result)){
  exit("Order added successfully!");
}
else{
  exit("Error connecting to database!");
}

?>

这是如此奇怪，因为数据被正确地添加到我的数据库和其他时候我使用相同的代码（用于用户注册）它没有任何问题。。。我检查了所有的东西，找不到问题。

$query="INSERT INTO orders (email, products_ordered, total_price) VALUES (?, ?, ?)";
$sql_sec=$db_connect->prepare($query);
$sql_sec->bind_param("ssi", $user_email, $products_ordered, $total_price);
$sql_sec->execute();
$result=$sql_sec->get_result();

if(mysqli_num_rows($result)){
  exit("Order added successfully!");
}
else{
  exit("Error connecting to database!");
}

我得到的错误是：

警告：mysqli \u num \u rows（）期望参数1是mysqli \u result，在第58行的c:\xampp\htdocs\dream pizza\add \u order.php中给出布尔值

连接到数据库时出错！