---
title: WindowEventHandlers.onmessage
slug: Web/API/WindowEventHandlers/onmessage
tags:
  - API
  - Event Handler
  - HTML DOM
  - Property
  - Reference
  - Window
  - WindowEventHandlers
  - events
  - onmessage
translation_of: Web/API/WindowEventHandlers/onmessage
---
<div>{{APIRef("HTML DOM")}}{{ SeeCompatTable() }}</div>

<p>{{domxref("WindowEventHandlers")}} ミックスインの <strong><code>onmessage</code></strong> プロパティは、オブジェクトが {{event("message")}} イベントを受け取るたびに呼び出される {{event("Event_handlers", "event handler")}} です。</p>

<h2 id="Syntax" name="Syntax">構文</h2>

<pre class="syntaxbox">window.addEventListener('message', function(event) { ... })
window.onmessage = function(event) { ... }</pre>

<h2 id="Specifications" name="Specifications">仕様</h2>

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">仕様</th>
   <th scope="col">状態</th>
   <th scope="col">コメント</th>
  </tr>
  <tr>
   <td>{{SpecName('HTML WHATWG','#handler-window-onmessage','onmessage')}}</td>
   <td>{{Spec2('HTML WHATWG')}}</td>
   <td>初期定義</td>
  </tr>
 </tbody>
</table>

<h2 id="Browser_compatibility" name="Browser_compatibility">ブラウザーの互換性</h2>

<div>


<p>{{Compat("api.WindowEventHandlers.onmessage")}}</p>
</div>