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• 范例
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

message event is fired on a MessagePort object when a message arrives on that channel.

冒泡	No
可取消	No
接口	MessageEvent
事件处理程序特性	onmessage

范例

Suppose a script creates a MessageChannel and sends one of the ports to a different browsing context, such as another <iframe> , using code like this:

const channel = new MessageChannel();
const myPort = channel.port1;
const targetFrame = window.top.frames[1];
const targetOrigin = 'https://example.org';
const messageControl = document.querySelector('#message');
const channelMessageButton = document.querySelector('#channel-message');
channelMessageButton.addEventListener('click', () => {
    myPort.postMessage(messageControl.value);
})
targetFrame.postMessage('init', targetOrigin, [channel.port2]);
					

The target can receive the port and start listening for messages on it using code like this:

window.addEventListener('message', (event) => {
    const myPort = event.ports[0];
    myPort.addEventListener('message', (event) => {
        received.textContent = event.data;
    });
    myPort.start();
});
					

Note that the listener must call MessagePort.start() before any messages will be delivered to this port. This is only needed when using the addEventListener() method: if the receiver uses onmessage instead, start() is called implicitly:

window.addEventListener('message', (event) => {
    const myPort = event.ports[0];
    myPort.onmessage = (event) => {
        received.textContent = event.data;
    };
});
					

规范

规范	状态
HTML 实时标准	实时标准

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
message event	Chrome 4	Edge 12	Firefox Yes	IE 10	Opera 10.6	Safari 5	WebView Android Yes	Chrome Android 18	Firefox Android No	Opera Android 11.5	Safari iOS 5.1	Samsung Internet Android 1.0

图例

完整支持

完整支持

不支持

不支持

另请参阅

• 相关事件： messageerror .
• Using channel messaging

元数据

• 最后修改： Apr 8, 2019

相关话题

1. MessagePort
2. 特性

   1. onmessage
   2. onmessageerror
3. 方法

   1. close()
   2. postMessage()
   3. start()
4. 事件

   1. message
   2. messageerror
5. 继承：

   1. EventTarget