Query-string encoding of a Javascript Object

Question

Do you know a fast and simple way to encode a Javascript Object into a string that I can pass via a GET Request?

No jQuery, no

Answer 1

This is a solution that will work for .NET backends out of the box. I have taken the primary answer of this thread and updated it to fit our .NET needs.

function objectToQuerystring(params) {
var result = '';

    function convertJsonToQueryString(data, progress, name) {
        name = name || '';
        progress = progress || '';
        if (typeof data === 'object') {
            Object.keys(data).forEach(function (key) {
                var value = data[key];
                if (name == '') {
                    convertJsonToQueryString(value, progress, key);
                } else {
                    if (isNaN(parseInt(key))) {
                        convertJsonToQueryString(value, progress, name + '.' + key);
                    } else {
                        convertJsonToQueryString(value, progress, name + '[' + key+ ']');
                    }
                }
            })
        } else {
            result = result ? result.concat('&') : result.concat('?');
            result = result.concat(`${name}=${data}`);
        }
    }

    convertJsonToQueryString(params);
    return result;
}

Answer 2

like this?

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

Edit: this one also converts recursive objects (using php "array" notation for the query string)

serialize = function(obj, prefix) {
  var str = [],
    p;
  for (p in obj) {
    if (obj.hasOwnProperty(p)) {
      var k = prefix ? prefix + "[" + p + "]" : p,
        v = obj[p];
      str.push((v !== null && typeof v === "object") ?
        serialize(v, k) :
        encodeURIComponent(k) + "=" + encodeURIComponent(v));
    }
  }
  return str.join("&");
}

console.log(serialize({
  foo: "hi there",
  bar: {
    blah: 123,
    quux: [1, 2, 3]
  }
}));
// foo=hi%20there&bar%5Bblah%5D=123&bar%5Bquux%5D%5B0%5D=1&bar%5Bquux%5D%5B1%5D=2&bar%5Bquux%5D%5B2%5D=3

Answer 3

Here's the coffeescript version of accepted answer. This might save time to someone.

serialize = (obj, prefix) ->
  str = []
  for p, v of obj
    k = if prefix then prefix + "[" + p + "]" else p
    if typeof v == "object"
      str.push(serialize(v, k))
    else
      str.push(encodeURIComponent(k) + "=" + encodeURIComponent(v))

  str.join("&")

Answer 4

use JSON.

take a look at this question for ideas on how to implement.

Answer 5

This one skips null/undefined values

export function urlEncodeQueryParams(data) {
    const params = Object.keys(data).map(key => data[key] ? `${encodeURIComponent(key)}=${encodeURIComponent(data[key])}` : '');
    return params.filter(value => !!value).join('&');
}

Answer 6

ES6 SOLUTION FOR QUERY STRING ENCODING OF A JAVASCRIPT OBJECT

const params = {
  a: 1,
  b: 'query stringify',
  c: null,
  d: undefined,
  f: '',
  g: { foo: 1, bar: 2 },
  h: ['Winterfell', 'Westeros', 'Braavos'],
  i: { first: { second: { third: 3 }}}
}

static toQueryString(params = {}, prefix) {
  const query = Object.keys(params).map((k) => {
    let key = k;
    const value = params[key];

    if (!value && (value === null || value === undefined || isNaN(value))) {
      value = '';
    }

    switch (params.constructor) {
      case Array:
        key = `${prefix}[]`;
        break;
      case Object:
        key = (prefix ? `${prefix}[${key}]` : key);
        break;
    }

    if (typeof value === 'object') {
      return this.toQueryString(value, key); // for nested objects
    }

    return `${key}=${encodeURIComponent(value)}`;
  });

  return query.join('&');
}

toQueryString(params)

"a=1&b=query%20stringify&c=&d=&f=&g[foo]=1&g[bar]=2&h[]=Winterfell&h[]=Westeros&h[]=Braavos&i[first][second][third]=3"