subscribe-event

Easiest way to subscribe and unsubscribe browser / node events

Usage no npm install needed!

<script type="module">
  import subscribeEvent from 'https://cdn.skypack.dev/subscribe-event';
</script>

README

Subscribe-event

Subscribe-event is the easiest way to subscribe either dom events in browser or node.js events.

Live example: http://xnimorz.github.io/subscribe-event/

Install

npm install --save subscribe-event
// or for yarn:
yarn add subscribe-event

Library support es6, CommonJs, AMD modules

Getting started

Step 1: import module:

import subscribe from "subscribe-event";

Step 2: call subscrube function:

const unsubscribe = subscribe(document, "scroll", () => {
  /* Do some job */
});

Step 3: call unsubscibe, which returned from subscribe function, to dispose:

  unsubscribe();

API

subscribe is a function, which receives 4 arguments:

  1. element — is a HTMLElement such as document.body, document, etc., Node.js object or any another object, that triggers events.
  2. event — is an event, such as scroll, click, mousemove etc.
  3. eventCallback — a function called when event triggers
  4. options — unessesary parameter, which provides more data to subscribe function. For example, when you using subscribe for HTMLElements you can capture events: subscibe(document.querySelector('#a'), 'click', () => console.log('clicked'), true)

Usage with React

import React, { Component } from "react";
import subscribe from "subscribe-event";

class MyAmazingComponent extends Component {
  componentDidMount() {
    this.unsubscribeScroll = subscribe(document, "scroll", () => {
      // do some job
    });
  }

  componentWillUnmount() {
    this.unsubscribeScroll();
  }

  render() {
    const { children } = this.props;

    return <div>{children}</div>;
  }
}

Subscribe-event is useful for capturing events:

import React, { Component } from "react";
import subscribe from "subscribe-event";

class MyAmazingComponent extends Component {
  componentDidMount() {
    this.unsubscribe = subscribe(
      document,
      "scroll",
      () => {
        // do some job
      },
      true
    );
  }

  componentWillUnmount() {
    this.unsubscribe();
  }

  render() {
    const { children } = this.props;

    return <div>{children}</div>;
  }
}

Examples

For example in browser:

import subscribe from "subscribe-event";

var element = document.querySelector(".my-button");

var unsubscribe = subscribe(element, "click", e => {
  console.log(e);
});

// code

unsubscribe();

or

import subscribe from "subscribe-event";

var unsubscribe = subscribe(document, "scroll", e => {
  console.log(e);
});

// code

unsubscribe();

This library supports old ie also (attachEvent/detachEvent).

You can define your custom event subscribe function:

import subscribe from 'subscribe-event';

var obj: {
  eventSubscribe: function() {...},
  eventUnsubscribe: function() {...}
}

var customSubscribe = subscribe.define('eventSubscribe', 'eventUnsubscribe');

var customUnsubscribe = customSubscribe(obj, event, handler);

// ...

customUnsubscribe();

By default subscribe-event works with: addEventListener, detachEvent, on