onmessage event handler of the MessagePort interface is an EventListener , called whenever an MessageEvent 类型 message is fired on the port — that is, when the port receives a message.

注意: 此特征可用于 Web 工作者 .

句法

channel.onmessage = function() { ... };
					

范例

In the following code block, you can see a new channel being created using the MessageChannel.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 — MessageChannel.port1 is listened to, to check when the message arrives.

var channel = new MessageChannel();
var para = document.querySelector('p');
var ifr = document.querySelector('iframe');
var 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;
}
					

For a full working example, see our channel messaging basic demo on Github ( run it live too ).

规范

规范 状态 注释
HTML 实时标准
The definition of 'onmessage' in that specification.
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
onmessage Chrome 4 Edge 12 Firefox Yes IE 10 Opera 10.6 Safari 5 WebView Android Yes Chrome Android 18 Firefox Android 不支持 No Opera Android 11 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

元数据

  • 最后修改:
  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
  6. HTML DOM 相关页面
    1. BeforeUnloadEvent
    2. DOMStringMap
    3. ErrorEvent
    4. GlobalEventHandlers
    5. HTMLAnchorElement
    6. HTMLAreaElement
    7. HTMLAudioElement
    8. HTMLBRElement
    9. HTMLBaseElement
    10. HTMLBaseFontElement
    11. HTMLBodyElement
    12. HTMLButtonElement
    13. HTMLCanvasElement
    14. HTMLContentElement
    15. HTMLDListElement
    16. HTMLDataElement
    17. HTMLDataListElement
    18. HTMLDialogElement
    19. HTMLDivElement
    20. HTMLDocument
    21. HTMLElement
    22. HTMLEmbedElement
    23. HTMLFieldSetElement
    24. HTMLFormControlsCollection
    25. HTMLFormElement
    26. HTMLFrameSetElement
    27. HTMLHRElement
    28. HTMLHeadElement
    29. HTMLHeadingElement
    30. HTMLHtmlElement
    31. HTMLIFrameElement
    32. HTMLImageElement
    33. HTMLInputElement
    34. HTMLIsIndexElement
    35. HTMLKeygenElement
    36. HTMLLIElement
    37. HTMLLabelElement
    38. HTMLLegendElement
    39. HTMLLinkElement
    40. HTMLMapElement
    41. HTMLMediaElement
    42. HTMLMetaElement
    43. HTMLMeterElement
    44. HTMLModElement
    45. HTMLOListElement
    46. HTMLObjectElement
    47. HTMLOptGroupElement
    48. HTMLOptionElement
    49. HTMLOptionsCollection
    50. HTMLOutputElement
    51. HTMLParagraphElement
    52. HTMLParamElement
    53. HTMLPictureElement
    54. HTMLPreElement
    55. HTMLProgressElement
    56. HTMLQuoteElement
    57. HTMLScriptElement
    58. HTMLSelectElement
    59. HTMLShadowElement
    60. HTMLSourceElement
    61. HTMLSpanElement
    62. HTMLStyleElement
    63. HTMLTableCaptionElement
    64. HTMLTableCellElement
    65. HTMLTableColElement
    66. HTMLTableDataCellElement
    67. HTMLTableElement
    68. HTMLTableHeaderCellElement
    69. HTMLTableRowElement
    70. HTMLTableSectionElement
    71. HTMLTemplateElement
    72. HTMLTextAreaElement
    73. HTMLTimeElement
    74. HTMLTitleElement
    75. HTMLTrackElement
    76. HTMLUListElement
    77. HTMLUnknownElement
    78. HTMLVideoElement
    79. HashChangeEvent
    80. 历史
    81. ImageData
    82. 定位
    83. MessageChannel
    84. MessageEvent
    85. Navigator
    86. NavigatorGeolocation
    87. NavigatorID
    88. NavigatorLanguage
    89. NavigatorOnLine
    90. NavigatorPlugins
    91. PageTransitionEvent
    92. Plugin
    93. PluginArray
    94. PopStateEvent
    95. PortCollection
    96. PromiseRejectionEvent
    97. RadioNodeList
    98. Transferable
    99. ValidityState
    100. Window
    101. WindowBase64
    102. WindowEventHandlers
    103. WindowTimers