The port1
read-only property of the MessageChannel
interface returns the first port of the message channel — the port attached to the context that originated the channel.
Note: This feature is available in Web Workers
The port1
read-only property of the MessageChannel
interface returns the first port of the message channel — the port attached to the context that originated the channel.
Note: This feature is available in Web Workers
A MessagePort
object, the first port of the channel, that is the port attached to the context that originated the channel.
In the following code block, you can see a new channel being created using the MessageChannel()
constructor. When the <iframe>
has loaded, we pass MessageChannel.port2
to the <iframe>
using MessagePort.postMessage
along with a message. The handleMessage
handler then responds to a message being sent back from the <iframe>
(using onmessage
), putting it into a paragraph. The handleMessage
method is associated to the port1
to listen when the message arrives.
js
const channel = new MessageChannel(); const para = document.querySelector("p"); const ifr = document.querySelector("iframe"); const otherWindow = ifr.contentWindow; ifr.addEventListener("load", iframeLoaded, false); function iframeLoaded() { otherWindow.postMessage("Hello from the main page!", "*", [channel.port2]); } channel.port1.onmessage = handleMessage; function handleMessage(e) { para.innerHTML = e.data; }
Specification |
---|
HTML Standard # dom-messagechannel-port1-dev |
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
port1 |
2 | 12 | 41 | 10 | 10.6 | 5 | 4.4 | 18 | 41 | 11 | 4.2 | 1.0 |
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https://developer.mozilla.org/en-US/docs/Web/API/MessageChannel/port1