javascript querystring code example

Example 1: javascript read query parameters

// example url: https://mydomain.com/?fname=johnny&lname=depp
const queryString = window.location.search;
console.log(queryString);
// ?fname=johnny&lname=depp

const urlParams = new URLSearchParams(queryString);

const firstName = urlParams.get('fname');
console.log(firstName);
// johnny

const lastName = urlParams.get('lname');
console.log(lastName);
// depp

Example 2: js query string

const urlParams = new URLSearchParams(window.location.search);
const myParam = urlParams.get('myParam');

Example 3: javascript get query parameter

function getUrlParameter(name) {
    name = name.replace(/[\[]/, '\\[').replace(/[\]]/, '\\]');
    var regex = new RegExp('[\\?&]' + name + '=([^&#]*)');
    var results = regex.exec(location.search);
    return results === null ? '' : decodeURIComponent(results[1].replace(/\+/g, ' '));
};

Example 4: get query string javascript nodejs

const querystring = require('querystring');
const url = "http://example.com/index.html?code=string&key=12&id=false";
const qs = "code=string&key=12&id=false";

console.log(querystring.parse(qs));
// > { code: 'string', key: '12', id: 'false' }

console.log(querystring.parse(url));

Example 5: string to query string javascript

serialize = function(obj) {
  var str = [];
  for (var p in obj)
    if (obj.hasOwnProperty(p)) {
      str.push(encodeURIComponent(p) + "=" + encodeURIComponent(obj[p]));
    }
  return str.join("&");
}

console.log(serialize({
  foo: "hi there",
  bar: "100%"
}));
// foo=hi%20there&bar=100%25