37 lines
925 B
JavaScript
37 lines
925 B
JavaScript
## Example: fetch
|
|
|
|
|
|
## Example: fetch
|
|
|
|
Promises are also returned by some built-in browser methods.
|
|
|
|
For instance, [fetch](https://fetch.spec.whatwg.org/#fetch-method) allows to load arbitrary content over the network. We can use it to send information to the server and load data from it.
|
|
|
|
The syntax is:
|
|
|
|
```js
|
|
let promise = fetch(url[, options]);
|
|
```
|
|
|
|
Here:
|
|
- `url` is the URL to load,
|
|
- `options` are various request options.
|
|
|
|
There are many options, full information about them is in the [spec](https://fetch.spec.whatwg.org/#requestinit), here we won't need them.
|
|
|
|
The promise returned by `fetch` resolves with the `response` object when the server responds.
|
|
|
|
The most important properties of `response` are:
|
|
- `status` -- HTTP-code: 200 for OK, 404 for "Page not found" etc.
|
|
- `headers` -- HTTP headers.
|
|
-
|
|
|
|
The important thing
|
|
|
|
|
|
```js run
|
|
fetch('/article/promise-chaining/1.html?speed=1')
|
|
.then(console.log);
|
|
```
|
|
|
|
|