问题描述

我正在尝试定期发送hello world！"从 Ratchet 教程向所有连接到聊天服务器的客户端发送消息

I'm trying to periodically send a "hello world!" message to all clients connected to the chat-server from the Ratchet tutorial

我将在这里发布所有代码:聊天.php:

I will post all of the code here: Chat.php:

<?php
namespace MyApp;
use RatchetMessageComponentInterface;
use RatchetConnectionInterface;

class Chat implements MessageComponentInterface {
    public $clients;

    public function __construct() {
        $this->clients = new SplObjectStorage;
            }

    public function onOpen(ConnectionInterface $conn) {
        // Store the new connection to send messages to later
        $this->clients->attach($conn);

        echo "New connection! ({$conn->resourceId})
";
    }

    //this worked but I don't want this behaviour
    public function onMessage(ConnectionInterface $from, $msg) {
        /*$numRecv = count($this->clients) - 1;
        echo sprintf('Connection %d sending message "%s" to %d other connection%s' . "
"
            , $from->resourceId, $msg, $numRecv, $numRecv == 1 ? '' : 's');

        foreach ($this->clients as $client) {
            if ($from !== $client) {
                // The sender is not the receiver, send to each client connected
                $client->send($msg);
            }
        }*/
    }

    public function onClose(ConnectionInterface $conn) {
        // The connection is closed, remove it, as we can no longer send it messages
        $this->clients->detach($conn);

        echo "Connection {$conn->resourceId} has disconnected
";
    }

    public function onError(ConnectionInterface $conn, Exception $e) {
        echo "An error has occurred: {$e->getMessage()}
";

        $conn->close();
    }
}

聊天服务器.php:

<?php
use RatchetServerIoServer;
use MyAppChat;

    require dirname(__DIR__) . '/vendor/autoload.php';

    $server = IoServer::factory(
        new Chat(),
        8080
    );

    $server->run();

为了测试我理解了多少文档，我在服务器的循环中添加了一个计时器

To test how much of the docs I understood , I added a timer to the server's loop

    <?php
    use RatchetServerIoServer;
    use MyAppChat;

        require dirname(__DIR__) . '/vendor/autoload.php';

        $server = IoServer::factory(
            new Chat(),
            8080
        );


        // My code here
        $server->loop->addPeriodicTimer(5, function () {
          echo  "custom loop timer working !";        
        });


        $server->run();

并且它在启动服务器后每五秒输出一次该字符串工作正常.

and it worked fine outputting that string every five seconds after starting the server.

现在我尝试这样做，尝试向存储在 MessageComponentInterface 中的客户端发送一条消息，该接口称为教程中的 Chat

Now I tried doing it like so, trying to send a message to clients stored in the MessageComponentInterface called Chat from the tutorial

$server->loop->addPeriodicTimer(5, function () {        
    foreach ($server->app->clients as $client) {                  
            $client->send("hello client");          
    }
});

但我得到 $server->app 为 NULL 这可能是因为我现在在 function() 块中.当谈到面向对象的 PHP 时，我不是专家，这个小项目将肯定对我有很大帮助.如何在计时器内访问名为 app 的服务器的 MessageComponentInterface 属性，然后将数据发送到存储在其中的客户端?

But I'm getting that $server->app is NULL which is probably because I'm now inside the function() block .I'm not an expert when it comes to Object oriented PHP, and this little project will sure help me a lot. How can I access the MessageComponentInterface called app property of the server inside the timer and then send data to the clients stored in there?

推荐答案

$server 没有在函数作用域中定义，父作用域的变量不会被继承到子作用域默认.闭包可以通过使用 use 语言结构从父作用域继承变量.

$server isn't defined in the function scope and variables from the parent scope don't get inherited to the child scope by default. Closures can inherit variables from the parent scope by using the use language construct.

$server->loop->addPeriodicTimer(5, function () use ($server) {        
    foreach ($server->app->clients as $client) {                  
            $client->send("hello client");          
    }
});

关于匿名函数(闭包)的更多信息:https://secure.php.net/manual/en/functions.anonymous.php
有关变量范围的更多信息:https://secure.php.net/manual/en/language.variables.scope.php

More information about anonymous functions (closures): https://secure.php.net/manual/en/functions.anonymous.php
More information about variables scope: https://secure.php.net/manual/en/language.variables.scope.php

这篇关于定期向 Ratchet 中的客户端发送消息的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持跟版网！