How to convert URL parameters to a JavaScript object?

Question

I have a string like this:

abc=foo&def=%5Basf%5D&xyz=5

How can I convert it into a JavaScript object like this?

{
          


        

Answer 1

Using phpjs

function parse_str(str, array) {
  //       discuss at: http://phpjs.org/functions/parse_str/
  //      original by: Cagri Ekin
  //      improved by: Michael White (http://getsprink.com)
  //      improved by: Jack
  //      improved by: Brett Zamir (http://brett-zamir.me)
  //      bugfixed by: Onno Marsman
  //      bugfixed by: Brett Zamir (http://brett-zamir.me)
  //      bugfixed by: stag019
  //      bugfixed by: Brett Zamir (http://brett-zamir.me)
  //      bugfixed by: MIO_KODUKI (http://mio-koduki.blogspot.com/)
  // reimplemented by: stag019
  //         input by: Dreamer
  //         input by: Zaide (http://zaidesthings.com/)
  //         input by: David Pesta (http://davidpesta.com/)
  //         input by: jeicquest
  //             note: When no argument is specified, will put variables in global scope.
  //             note: When a particular argument has been passed, and the returned value is different parse_str of PHP. For example, a=b=c&d====c
  //             test: skip
  //        example 1: var arr = {};
  //        example 1: parse_str('first=foo&second=bar', arr);
  //        example 1: $result = arr
  //        returns 1: { first: 'foo', second: 'bar' }
  //        example 2: var arr = {};
  //        example 2: parse_str('str_a=Jack+and+Jill+didn%27t+see+the+well.', arr);
  //        example 2: $result = arr
  //        returns 2: { str_a: "Jack and Jill didn't see the well." }
  //        example 3: var abc = {3:'a'};
  //        example 3: parse_str('abc[a][b]["c"]=def&abc[q]=t+5');
  //        returns 3: {"3":"a","a":{"b":{"c":"def"}},"q":"t 5"}

  var strArr = String(str)
    .replace(/^&/, '')
    .replace(/&$/, '')
    .split('&'),
    sal = strArr.length,
    i, j, ct, p, lastObj, obj, lastIter, undef, chr, tmp, key, value,
    postLeftBracketPos, keys, keysLen,
    fixStr = function(str) {
      return decodeURIComponent(str.replace(/\+/g, '%20'));
    };

  if (!array) {
    array = this.window;
  }

  for (i = 0; i < sal; i++) {
    tmp = strArr[i].split('=');
    key = fixStr(tmp[0]);
    value = (tmp.length < 2) ? '' : fixStr(tmp[1]);

    while (key.charAt(0) === ' ') {
      key = key.slice(1);
    }
    if (key.indexOf('\x00') > -1) {
      key = key.slice(0, key.indexOf('\x00'));
    }
    if (key && key.charAt(0) !== '[') {
      keys = [];
      postLeftBracketPos = 0;
      for (j = 0; j < key.length; j++) {
        if (key.charAt(j) === '[' && !postLeftBracketPos) {
          postLeftBracketPos = j + 1;
        } else if (key.charAt(j) === ']') {
          if (postLeftBracketPos) {
            if (!keys.length) {
              keys.push(key.slice(0, postLeftBracketPos - 1));
            }
            keys.push(key.substr(postLeftBracketPos, j - postLeftBracketPos));
            postLeftBracketPos = 0;
            if (key.charAt(j + 1) !== '[') {
              break;
            }
          }
        }
      }
      if (!keys.length) {
        keys = [key];
      }
      for (j = 0; j < keys[0].length; j++) {
        chr = keys[0].charAt(j);
        if (chr === ' ' || chr === '.' || chr === '[') {
          keys[0] = keys[0].substr(0, j) + '_' + keys[0].substr(j + 1);
        }
        if (chr === '[') {
          break;
        }
      }

      obj = array;
      for (j = 0, keysLen = keys.length; j < keysLen; j++) {
        key = keys[j].replace(/^['"]/, '')
          .replace(/['"]$/, '');
        lastIter = j !== keys.length - 1;
        lastObj = obj;
        if ((key !== '' && key !== ' ') || j === 0) {
          if (obj[key] === undef) {
            obj[key] = {};
          }
          obj = obj[key];
        } else { // To insert new dimension
          ct = -1;
          for (p in obj) {
            if (obj.hasOwnProperty(p)) {
              if (+p > ct && p.match(/^\d+$/g)) {
                ct = +p;
              }
            }
          }
          key = ct + 1;
        }
      }
      lastObj[key] = value;
    }
  }
}

Answer 2

A concise solution:

location.search
  .slice(1)
  .split('&')
  .map(p => p.split('='))
  .reduce((obj, pair) => {
    const [key, value] = pair.map(decodeURIComponent);
    obj[key] = value;
    return obj;
  }, {});

Answer 3

//under ES6 
const getUrlParamAsObject = (url = window.location.href) => {
    let searchParams = url.split('?')[1];
    const result = {};
    //in case the queryString is empty
    if (searchParams!==undefined) {
        const paramParts = searchParams.split('&');
        for(let part of paramParts) {
            let paramValuePair = part.split('=');
            //exclude the case when the param has no value
            if(paramValuePair.length===2) {
                result[paramValuePair[0]] = decodeURIComponent(paramValuePair[1]);
            }
        }

    }
    return result;
}

Answer 4

ES6 one liner (if we can call it that way seeing the long line)

[...new URLSearchParams(location.search).entries()].reduce((prev, [key,val]) => {prev[key] = val; return prev}, {})

Answer 5

One of the simplest way to do this using URLSearchParam interface.

Below is the working code snippet:

let paramObj={},
    querystring=window.location.search,
    searchParams = new URLSearchParams(querystring);    

  //*** :loop to add key and values to the param object.
 searchParams.forEach(function(value, key) {
      paramObj[key] = value;
   });

Answer 6

There's a lightweight library called YouAreI.js that's tested and makes this really easy.

YouAreI = require('YouAreI')
uri = new YouAreI('http://user:pass@www.example.com:3000/a/b/c?d=dad&e=1&f=12.3#fragment');

uri.query_get() => { d: 'dad', e: '1', f: '12.3' }