This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for the proper prefixes to use in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the spec changes.
The type
read-only property of the Response
interface contains the type of the response. It can be one of the following:
basic
: Normal, same origin response, with all headers exposed except “Set-Cookie” and “Set-Cookie2″.cors
: Response was received from a valid cross-origin request. Certain headers and the body may be accessed.error
: Network error. No useful information describing the error is available. The Response’s status is 0, headers are empty and immutable. This is the type for a Response obtained fromResponse.error()
.opaque
: Response for “no-cors” request to cross-origin resource. Severely restricted.
Note: An "error" Response never really gets exposed to script: such a response to a fetch()
would reject the promise.
Syntax
var myType = response.type;
Value
A ResponseType
string indicating the type of the response.
Example
In our Fetch Response example (see Fetch Response live) we create a new Request
object using the Request()
constructor, passing it a JPG path. We then fetch this request using fetch()
, extract a blob from the response using Body.blob
, create an object URL out of it using URL.createObjectURL
, and display this in an <img>
.
Note that at the top of the fetch()
block we log the response type
to the console.
var myImage = document.querySelector('img'); var myRequest = new Request('flowers.jpg'); fetch(myRequest).then(function(response) { console.log(response.type); // returns basic by default response.blob().then(function(myBlob) { var objectURL = URL.createObjectURL(myBlob); myImage.src = objectURL; }); });
Specifications
Specification | Status | Comment |
---|---|---|
Fetch The definition of 'type' in that specification. |
Living Standard | Initial definition |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|
Basic support | 42 41[1] |
39 (39) 34[2] |
Not supported |
29 |
Not supported |
Feature | Android | Firefox Mobile (Gecko) | Firefox OS (Gecko) | IE Phone | Opera Mobile | Safari Mobile | Chrome for Android |
---|---|---|---|---|---|---|---|
Basic support | Not supported | Not supported | Not supported | Not supported | Not supported | Not supported | Not supported |
[1] The implementation of this feature is behind the "Experimental Web Platform Features" preference in chrome://flags
.
[2] The implementation of this feature is behind the preference dom.fetch.enabled
in about:config
, defaulting to false
.