URLSearchParams Polyfill

This is a polyfill library for JavaScript's URLSearchParams class.

Features

• Implemented all features from MDN document.
• Can use for both browsers and Node.js.
• Detect if browsers have full support for URLSearchParams and extend it
• Compatible with IE8 and above

Installation

This can also be installed with npm.

$ npm install url-search-params-polyfill --save

For Babel and ES2015+, make sure to import the file:

import 'url-search-params-polyfill';

For ES5:

require('url-search-params-polyfill');

For browser, copy the index.js file to your project, and add a script tag in your html:

<script src="index.js"></script>

Usage

Use URLSearchParams directly. You can instantiate a new instance of URLSearchParams from a string or an object.

// new an empty object
var search1 = new URLSearchParams();
 
// from a string
var search2 = new URLSearchParams("id=1&from=home");
 
// from an object
var search3 = new URLSearchParams({ id: 1, from: "home" });
 
// from location.search, will remove first "?" automatically
var search4 = new URLSearchParams(window.location.search);
 
// from anther URLSearchParams object
var search5 = new URLSearchParams(search2);

append

var search = new URLSearchParams();
 
search.append("id", 1);

delete

search.delete("id");

get

search.get("id");

getAll

search.getAll("id");

has

search.has("id");

set

search.set("id", 2);

toString

search.toString();

sort

search.sort();

forEach

search.forEach(function (item) {
  console.log(item);
});

keys

for (var key of search.keys()) {
  console.log(key);
}

values

for (var value of search.values()) {
  console.log(value);
}

for...of

for (var item of search) {
  console.log('key: ' + item[0] + ', ' + 'value: ' + item[1]);
}

Known Issues

Use with fetch (#18)

Via fetch spec, when passing a URLSearchParams object as a request body, the request should add a header with Content-Type: application/x-www-form-urlencoded; charset=UTF-8, but browsers which have fetch support and not URLSearchParams support do not have this behavior.

Via the data of caniuse, there are many browsers which support fetch but not URLSearchParams:

If you want to be compatible with these browsers, you should add a Content-Type header manually:

function myFetch(url, { headers = {}, body }) {
    headers = headers instanceof Headers ? headers : new Headers(headers);
    
    if (body instanceof URLSearchParams) {
        headers.set('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8');
    }
    
    fetch(url, {
        headers,
        body
    });
}

LICENSE

MIT license