W72crm_web-master/node_modules/throttle-debounce/README.md

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2025-05-27 11:25:53 +08:00
# throttle-debounce
[![Build Status][ci-img]][ci]
[![BrowserStack Status][browserstack-img]][browserstack]
[![Mentioned in Awesome Micro npm Packages][awesome-img]][awesome]
Throttle and debounce functions.
This module is the same as [jquery-throttle-debounce][jquery-throttle-debounce]
([with some differences](#differences-with-original-module)), but its
transferred to ES Modules and CommonJS format.
## Install
```sh
npm install throttle-debounce --save
```
## Usage
### `throttle`
```js
import { throttle } from 'throttle-debounce';
const throttleFunc = throttle(1000, false, (num) => {
console.log('num:', num);
});
// Can also be used like this, because noTrailing is false by default
const throttleFunc = throttle(1000, (num) => {
console.log('num:', num);
});
throttleFunc(1); // Will execute the callback
throttleFunc(2); // Wont execute callback
throttleFunc(3); // Wont execute callback
// Will execute the callback, because noTrailing is false,
// but if we set noTrailing to true, this callback wont be executed
throttleFunc(4);
setTimeout(() => {
throttleFunc(10); // Will execute the callback
}, 1200);
// Output
// num: 1
// num: 4
// num: 10
```
### `debounce`
```js
import { debounce } from 'throttle-debounce';
const debounceFunc = debounce(1000, false, (num) => {
console.log('num:', num);
});
// Can also be used like this, because atBegin is false by default
const debounceFunc = debounce(1000, (num) => {
console.log('num:', num);
});
// Wont execute the callback, because atBegin is false,
// but if we set atBegin to true, this callback will be executed.
debounceFunc(1);
debounceFunc(2); // Wont execute callback
debounceFunc(3); // Wont execute callback
// Will execute the callback,
// but if we set atBegin to true, this callback wont be executed.
debounceFunc(4);
setTimeout(() => {
debounceFunc(10); // Will execute the callback
}, 1200);
// Output
// num: 4
// num: 10
```
### Cancelling
Debounce and throttle can both be cancelled by calling the `cancel` function.
```js
const throttleFunc = throttle(300, () => {
// Throttled function
});
throttleFunc.cancel();
const debounceFunc = debounce(300, () => {
// Debounced function
});
debounceFunc.cancel();
```
The logic that is being throttled or debounced will no longer be called.
## API
### throttle(delay, noTrailing, callback, debounceMode)
Returns: `Function`
Throttle execution of a function. Especially useful for rate limiting execution
of handlers on events like resize and scroll.
#### delay
Type: `Number`
A zero-or-greater delay in milliseconds. For event callbacks, values around 100
or 250 (or even higher) are most useful.
#### noTrailing
Type: `Boolean`
Optional, defaults to false. If noTrailing is true, callback will only execute
every `delay` milliseconds while the throttled-function is being called. If
noTrailing is false or unspecified, callback will be executed one final time
after the last throttled-function call. (After the throttled-function has not
been called for `delay` milliseconds, the internal counter is reset)
#### callback
Type: `Function`
A function to be executed after delay milliseconds. The `this` context and all
arguments are passed through, as-is, to `callback` when the throttled-function
is executed.
#### debounceMode
Type: `Boolean`
If `debounceMode` is true (at begin), schedule `clear` to execute after `delay`
ms. If `debounceMode` is false (at end), schedule `callback` to execute after
`delay` ms.
### debounce(delay, atBegin, callback)
Returns: `Function`
Debounce execution of a function. Debouncing, unlike throttling, guarantees that
a function is only executed a single time, either at the very beginning of a
series of calls, or at the very end.
#### delay
Type: `Number`
A zero-or-greater delay in milliseconds. For event callbacks, values around 100
or 250 (or even higher) are most useful.
#### atBegin
Type: `Boolean`
Optional, defaults to false. If `atBegin` is false or unspecified, callback will
only be executed `delay` milliseconds after the last debounced-function call. If
`atBegin` is true, callback will be executed only at the first
debounced-function call. (After the throttled-function has not been called for
`delay` milliseconds, the internal counter is reset).
#### callback
Type: `Function`
A function to be executed after delay milliseconds. The `this` context and all
arguments are passed through, as-is, to `callback` when the debounced-function
is executed.
## Differences with original module
- Dependancy on jQuery is removed, so if you rely on GUIDs set by jQuery, plan
accordingly
- There is no standalone version available, so dont rely on `$.throttle` and
`$.debounce` to be available
## Browser support
Tested in IE9+ and all modern browsers.
## Test
For automated tests, run `npm run test:automated` (append `:watch` for watcher
support).
## License
<!-- prettier-ignore-start -->
**Original module license:** Copyright (c) 2010 "Cowboy" Ben Alman (Dual licensed under the MIT and GPL licenses. http://benalman.com/about/license/)
**This module license:** MIT © [Ivan Nikolić](http://ivannikolic.com)
[ci]: https://travis-ci.org/niksy/throttle-debounce
[ci-img]: https://travis-ci.org/niksy/throttle-debounce.svg?branch=master
[browserstack]: https://www.browserstack.com/
[browserstack-img]: https://www.browserstack.com/automate/badge.svg?badge_key=QWo5dGJqTzNkMWFnVXZqYzNvVDF1Q2p2Mm84Skc5ZTZFUUlnYkdEcFhQTT0tLTc1bVR3U284Uk9LZEFiSGR0NS8rY1E9PQ==--4a20321e30f225033ed6840c2fb71c6d1a8d2d1a
[awesome]: https://github.com/parro-it/awesome-micro-npm-packages
[awesome-img]: https://awesome.re/mentioned-badge.svg
[jquery-throttle-debounce]: https://github.com/cowboy/jquery-throttle-debounce
<!-- prettier-ignore-end -->