files/zh-tw/orphaned/web/api/body/index.html


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100

---
title: Body
slug: orphaned/Web/API/Body
tags:
  - API
  - BODY
  - Experimental
  - Fetch
  - Fetch API
  - Interface
  - NeedsTranslation
  - Reference
  - TopicStub
  - request
translation_of: Web/API/Body
original_slug: Web/API/Body
---
<div>{{ APIRef("Fetch") }}</div>

<p><span class="seoSummary">The <strong><code>Body</code></strong> {{glossary("mixin")}} of the <a href="/en-US/docs/Web/API/Fetch_API">Fetch API</a> represents the body of the response/request, allowing you to declare what its content type is and how it should be handled.</span></p>

<p><code>Body</code> is implemented by both {{domxref("Request")}} and {{domxref("Response")}}. This provides these objects with an associated <dfn>body</dfn> (a <a href="/en-US/docs/Web/API/Streams_API">stream</a>), a <dfn>used flag</dfn> (initially unset), and a <dfn>MIME type</dfn> (initially the empty byte sequence).</p>

<h2 id="Properties">Properties</h2>

<dl>
 <dt>{{domxref("Body.body")}} {{readonlyInline}}</dt>
 <dd>A simple getter used to expose a {{domxref("ReadableStream")}} of the body contents.</dd>
 <dt>{{domxref("Body.bodyUsed")}} {{readonlyInline}}</dt>
 <dd>A {{domxref("Boolean")}} that indicates whether the body has been read.</dd>
</dl>

<h2 id="Methods">Methods</h2>

<dl>
 <dt>{{domxref("Body.arrayBuffer()")}}</dt>
 <dd>Takes a {{domxref("Response")}} stream and reads it to completion. It returns a promise that resolves with an {{domxref("ArrayBuffer")}}.</dd>
 <dt>{{domxref("Body.blob()")}}</dt>
 <dd>Takes a {{domxref("Response")}} stream and reads it to completion. It returns a promise that resolves with a {{domxref("Blob")}}.</dd>
 <dt>{{domxref("Body.formData()")}}</dt>
 <dd>Takes a {{domxref("Response")}} stream and reads it to completion. It returns a promise that resolves with a {{domxref("FormData")}} object.</dd>
 <dt>{{domxref("Body.json()")}}</dt>
 <dd>Takes a {{domxref("Response")}} stream and reads it to completion. It returns a promise that resolves with the result of parsing the body text as {{jsxref("JSON")}}.</dd>
 <dt>{{domxref("Body.text()")}}</dt>
 <dd>Takes a {{domxref("Response")}} stream and reads it to completion. It returns a promise that resolves with a {{domxref("USVString")}} (text). The response is <em>always</em> decoded using UTF-8.</dd>
</dl>

<h2 id="Examples">Examples</h2>

<p>The example below uses a simple fetch call to grab an image and display it in an {{htmlelement("img")}} tag. You'll notice that since we are requesting an image, we need to run {{domxref("Body.blob","Body.blob()")}} ({{domxref("Response")}} implements body) to give the response its correct MIME type.</p>

<h3 id="HTML_Content">HTML Content</h3>

<pre class="brush: html">&lt;img class="my-image" src="https://wikipedia.org/static/images/project-logos/frwiki-1.5x.png"&gt;
</pre>

<h3 id="JS_Content">JS Content</h3>

<pre class="brush: js">var myImage = document.querySelector('.my-image');
fetch('https://upload.wikimedia.org/wikipedia/commons/7/77/Delete_key1.jpg')
	.then(res =&gt; res.blob())
	.then(res =&gt; {
		var objectURL = URL.createObjectURL(res);
		myImage.src = objectURL;
});</pre>

<p>{{ EmbedLiveSample('Examples', '100%', '250px') }}</p>

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

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">Specification</th>
   <th scope="col">Status</th>
   <th scope="col">Comment</th>
  </tr>
  <tr>
   <td>{{SpecName('Fetch','#body-mixin','Body')}}</td>
   <td>{{Spec2('Fetch')}}</td>
   <td> </td>
  </tr>
 </tbody>
</table>

<h2 id="Browser_compatibility">Browser compatibility</h2>


<p>{{Compat("api.Body")}}</p>

<h2 id="See_also">See also</h2>

<ul>
 <li><a href="/en-US/docs/Web/API/ServiceWorker_API">ServiceWorker API</a></li>
 <li><a href="/en-US/docs/Web/HTTP/Access_control_CORS">HTTP access control (CORS)</a></li>
 <li><a href="/en-US/docs/Web/HTTP">HTTP</a></li>
</ul>

<p> </p>