headers
只读特性在
Request
interface contains the
头
object associated with the request.
var myHeaders = request.headers;
A
头
对象。
In the following snippet, we create a new request using the
Request.Request()
constructor (for an image file in the same directory as the script), then save the request headers in a variable:
var myRequest = new Request('flowers.jpg');
var myHeaders = myRequest.headers; // Headers {}
To add a header to the
头
object we use
Headers.append
; we then create a new
Request
along with a 2nd init parameter, passing headers in as an init option:
var myHeaders = new Headers();
myHeaders.append('Content-Type', 'image/jpeg');
var myInit = {
method: 'GET',
headers: myHeaders,
mode: 'cors',
cache: 'default'
};
var myRequest = new Request('flowers.jpg', myInit);
myContentType = myRequest.headers.get('Content-Type'); // returns 'image/jpeg'
| 规范 | 状态 | 注释 |
|---|---|---|
|
Fetch
The definition of 'headers' in that specification. |
实时标准 | 初始定义 |
| 桌面 | 移动 | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
headers
|
Chrome
42
|
Edge 14 |
Firefox
39
|
IE No |
Opera
29
|
Safari No | WebView Android No | Chrome Android 42 — 46 | Firefox Android No |
Opera Android
29
|
Safari iOS No | Samsung Internet Android 4.0 — 5.0 |
完整支持
不支持
实验。期望将来行为有所改变。
用户必须明确启用此特征。