使用MessageChannel HTML5进行Web Workers通信

Question

我想实现网络工作者之间的沟通.我阅读了W3C文档,我发现MessageChannel是其中一种方法,但在阅读MessageChannel时,我无法理解如何使用messagechannel实现工作者之间的通信.

我从MSDN得到了这个

http://msdn.microsoft.com/en-in/library/ie/hh673525(v=vs.85).aspx

这里也没有适当的文档.

我需要知道,我如何使用MessageChannel与webworkers沟通？

这是演示抛出DATA_CLONE_ERR

var worker = new Worker("sub1_worker.js");
    worker.onmessage = function(e) {
        $("#log").append("<br>" + e.data);
    }
    var channel = new MessageChannel();

    worker.postMessage("ping", [channel.port2]);

    channel.port1.onmessage = function(event) {
        // Message is in event.data
        alert("Message is: " + event.data);
    }

    channel.port1.postMessage('hello');



    $("#send1").click(function() {
        var msg = $("#msg").val();
        if (msg && msg != "start")
            worker.postMessage("ping2");

        $("#msg").val("");

    })
    $("#send2").click(function() {
        var msg = $("#msg").val();
        if (msg && msg != "start")
            worker.postMessage("ping3",[channel.port2]);
        $("#msg").val("");

    })

和工人

onmessage = getMessage;

function getMessage(e){

    if(e.ports[0])
    e.ports[0].postMessage("msg from sub worker 1 "+ e.data);
    else
    postMessage("msg from sub worker 1 "+ e.data);
}

Answer 1

这里有一个关于如何在两个worker之间设置它的纯javascript中的一个干净的例子:

在主线程中:

function setup(){
    var channel = new MessageChannel();
    var worker1 = new Worker("worker1.js");
    var worker2 = new Worker("worker2.js");

    // Setup the connection: Port 1 is for worker 1
    worker1.postMessage({
        command : "connect",
    },[ channel.port1 ]);

    // Setup the connection: Port 2 is for worker 2
    worker2.postMessage({
        command : "connect",
    },[ channel.port2 ]);

    worker1.postMessage({
        command: "forward",
        message: "this message is forwarded to worker 2"
    });
}

在worker1.js:

var worker2port;
var onMessageFromWorker2 = function( event ){
    console.log("Worker 1 received a message from worker 2: " + event.data);

    //To send something back to worker 2
    //worker2port.postMessage("");
};

self.onmessage = function( event ) {
    switch( event.data.command )
    {
        // Setup connection to worker 2
        case "connect":
            worker2port = event.ports[0];
            worker2port.onmessage = onMessageFromWorker2;
            break;

        // Forward messages to worker 2
        case "forward":
            // Forward messages to worker 2
            worker2port.postMessage( event.data.message );
            break;

        //handle other messages from main
        default:
            console.log( event.data );
    }
};

在 worker2.js

var worker1port;
var onMessageFromWorker1 = function( event ){
    console.log("Worker 2 received a message from worker 1: " + event.data);

    //To send something back to worker 1
    //worker1port.postMessage("");
};

    self.onmessage = function( event ) {
    switch( event.data.command )
    {
        // Setup connection to worker 1
        case "connect":
            worker1port = event.ports[0];
            worker1port.onmessage = onMessageFromWorker1;
            break;

        // Forward messages to worker 1
        case "forward":
            // Forward messages to worker 1
            worker1port.postMessage( event.data.message );
            break;

        //handle other messages from main
        default:
            console.log( event.data );
    }
};

这显示了如何处理来自主线程的消息,如何将消息从主线程转发给另一个工作线以及如何在不涉及主线程的情况下直接在工作线程之间进行通信.

Answer 2

在 MessageChannel API 上工作了一段时间后。我找到了使用 MessageChannel 与网络工作者进行通信的解决方案。这是工作代码的演示。