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 json() method of the Body mixin takes a Response stream and reads it to completion. It returns a promise that resolves with an object literal containing the JSON data.
Syntax
response.json().then(function(json) {
// do something with your JSON
});
Parameters
None.
Returns
A promise that resolves with an object literal containing the JSON data.
Example
In our fetch json example (run fetch json live), we create a new request using the Request.Request constructor, then use it to fetch a .json file. When the fetch is successful, we read our JSON out of the response using json(), then read values out of the JSON as you'd expect and insert them into list items to display our product data.
var myList = document.querySelector('ul');
var myRequest = new Request('products.json');
fetch(myRequest).then(function(response) {
return response.json().then(function(json) {
for(i = 0; i < json.products.length; i++) {
var listItem = document.createElement('li');
listItem.innerHTML = '<strong>' + json.products[i].Name + '</strong> can be found in ' + json.products[i].Location + '. Cost: <strong>£' + json.products[i].Price + '</strong>';
myList.appendChild(listItem);
}
});
});
Specifications
| Specification | Status | Comment |
|---|---|---|
| Fetch The definition of 'json()' in that specification. |
Living Standard |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|
| Basic support | 42 [1] |
39 (39) [2] | Not supported |
29 [3] |
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] Behind a preference in version 41.
[2] Behind a preference starting with version 34.
[3] Behind a preference in version 28.