致命错误消息

Question

内容类型：text / html

致命错误：在 /home/content/18/8476518/html/training/emailOverdo.php 行上的非对象上调用成员函数fetch_object（）< b> 88

这是什么意思？！

$courses[] = array('name' => $obj->name, 'length' => $obj->length);
} else {
    $query = "SELECT address FROM email LEFT JOIN managers ON (email.id=managers.person_id) WHERE branch_id='".$branch_id."' AND tier='1' AND email.category='2'";
    $managers = $db->query($query);
    while($manager = $managers->fetch_object())
    {
        notifyManager($manager->address, $courses, $first_name, $last_name, $day);
    }

Answer 1

您的查询可能会返回null或false（取决于您的数据库类）

您的查询错误或者您没有可以选择的数据。

你要检查null的$经理或错误案例中的预期：

if ($managers !== null) {
    //while()
}

Answer 2

示例 这是你的dbc类

<?php

class dbc {

    public $dbserver = 'server';
    public $dbusername = 'user';
    public $dbpassword = 'pass';
    public $dbname = 'db';

    function openDb() {    
        try {
            $db = new PDO('mysql:host=' . $this->dbserver . ';dbname=' . $this->dbname . ';charset=utf8', '' . $this->dbusername . '', '' . $this->dbpassword . '');
        } catch (PDOException $e) {
            die("error, please try again");
        }        
        return $db;
    }

    function getAllData($qty) {
        //prepared query to prevent SQL injections
        $query = "select * from TABLE where qty = ?";
        $stmt = $this->openDb()->prepare($query);
        $stmt->bindValue(1, $qty, PDO::PARAM_INT);
        $stmt->execute();
        $rows = $stmt->fetchAll(PDO::FETCH_ASSOC);
        return $rows;
    }    
?>

你的PHP页面：

<?php 
require "dbc.php";
$db = new dbc;

$getList = $db->getAllData(25);

foreach ($getList as $key=> $row) {
         echo $row['columnName'] .' key: '. $key;
    }