Query String Problem

implode-explode.js

// Implode/Explode Approach

function queryString (str, param, value) {
  var output = ""; 
 
  splitString = str.split('?');
  baseURL = splitString[0];
  params = splitString[1].split('&');
  ctr = 0;
  params.forEach(function(p) {
    if (p.split('=')[0] == param) {
      p = param + '=' + value;
    }
    else {
      ctr++;
    }
  });
  
  if (ctr == params.length)
    params.push(param + '=' + value);
  
  output = baseURL + '?' + params.join("&");
  
  return output;
}

console.log(queryString("http://aniketpant.com/abc?a=1&b=2", 'c', '10'));

console.log(queryString("http://aniketpant.com/abc?a=1&b=2&c=25", 'c', '10'));

regex.js

// Regex Approach

function queryString (str, param, value) {
  var output = ""; 
  var regex = /http\:\/\/aniketpant\.com\/abc\?(\S+)/;
  var params = regex.exec(str)[1]; // list of paramenter
  
  return params;
}

console.log(queryString("http://aniketpant.com/abc?a=1&b=2", 'c', '10'));

console.log(queryString("http://aniketpant.com/abc?a=1&b=2&c=25", 'c', '10'));