PHP+Ajax method to detect network connection status in real time

In web development, sometimes we need to detect the user's network connection status in real time so that we can take appropriate actions when the network is disconnected or reconnected. In this article, I will introduce how to use PHP and Ajax to implement the function of real-time detection of network connection status.

First, we need to create a PHP file that handles Ajax requests and returns network connection status. We can name this file "check_connection.php". Here is a simple example code:

<?php
    // 检测网络连接状态的函数
    function checkConnection() {
   
    
    
        $connected = @fsockopen("www.example.com", 80