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 other frameworks - just plain Javascript :)
Query-string encoding of a Javascript Object
Viewed 554796
49 Answers
In ES7 you can write this in one line:
const serialize = (obj) => (Object.entries(obj).map(i => [i[0], encodeURIComponent(i[1])].join('=')).join('&'))
const toQueryString = obj => "?".concat(Object.keys(obj).map(e => `${encodeURIComponent(e)}=${encodeURIComponent(obj[e])}`).join("&"));
const data = {
offset: 5,
limit: 10
};
toQueryString(data); // => ?offset=5&limit=10
Or Use Pre Defined Feature
const data = {
offset: 5,
limit: 10
};
new URLSearchParams(data).toString(); // => ?offset=5&limit=10
Note
Both Above Methods will Set Value as null if not present if you want not to set query param if value is null then use
const toQueryString = obj => "?".concat(Object.keys(obj).map(e => obj[e] ? `${encodeURIComponent(e)}=${encodeURIComponent(obj[e])}` : null).filter(e => !!e).join("&"));
const data = {
offset: null,
limit: 10
};
toQueryString(data); // => "?limit=10" else with above methods "?offset=null&limit=10"
You Can Freely Use Any Method
Single line to convert Object into Query String in case somebody need it again
let Objs = { a: 'obejct-a', b: 'object-b' }
Object.keys(objs).map(key => key + '=' + objs[key]).join('&')
// result will be a=object-a&b=object-b
I made a comparison of JSON stringifiers and the results are as follows:
JSON: {"_id":"5973782bdb9a930533b05cb2","isActive":true,"balance":"$1,446.35","age":32,"name":"Logan Keller","email":"logankeller@artiq.com","phone":"+1 (952) 533-2258","friends":[{"id":0,"name":"Colon Salazar"},{"id":1,"name":"French Mcneil"},{"id":2,"name":"Carol Martin"}],"favoriteFruit":"banana"}
Rison: (_id:'5973782bdb9a930533b05cb2',age:32,balance:'$1,446.35',email:'logankeller@artiq.com',favoriteFruit:banana,friends:!((id:0,name:'Colon Salazar'),(id:1,name:'French Mcneil'),(id:2,name:'Carol Martin')),isActive:!t,name:'Logan Keller',phone:'+1 (952) 533-2258')
O-Rison: _id:'5973782bdb9a930533b05cb2',age:32,balance:'$1,446.35',email:'logankeller@artiq.com',favoriteFruit:banana,friends:!((id:0,name:'Colon Salazar'),(id:1,name:'French Mcneil'),(id:2,name:'Carol Martin')),isActive:!t,name:'Logan Keller',phone:'+1 (952) 533-2258'
JSURL: ~(_id~'5973782bdb9a930533b05cb2~isActive~true~balance~'!1*2c446.35~age~32~name~'Logan*20Keller~email~'logankeller*40artiq.com~phone~'*2b1*20*28952*29*20533-2258~friends~(~(id~0~name~'Colon*20Salazar)~(id~1~name~'French*20Mcneil)~(id~2~name~'Carol*20Martin))~favoriteFruit~'banana)
QS: _id=5973782bdb9a930533b05cb2&isActive=true&balance=$1,446.35&age=32&name=Logan Keller&email=logankeller@artiq.com&phone=+1 (952) 533-2258&friends[0][id]=0&friends[0][name]=Colon Salazar&friends[1][id]=1&friends[1][name]=French Mcneil&friends[2][id]=2&friends[2][name]=Carol Martin&favoriteFruit=banana
URLON: $_id=5973782bdb9a930533b05cb2&isActive:true&balance=$1,446.35&age:32&name=Logan%20Keller&email=logankeller@artiq.com&phone=+1%20(952)%20533-2258&friends@$id:0&name=Colon%20Salazar;&$id:1&name=French%20Mcneil;&$id:2&name=Carol%20Martin;;&favoriteFruit=banana
QS-JSON: isActive=true&balance=%241%2C446.35&age=32&name=Logan+Keller&email=logankeller%40artiq.com&phone=%2B1+(952)+533-2258&friends(0).id=0&friends(0).name=Colon+Salazar&friends(1).id=1&friends(1).name=French+Mcneil&friends(2).id=2&friends(2).name=Carol+Martin&favoriteFruit=banana
The shortest among them is URL Object Notation.
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"
It seems that till now nobody mention another popular library qs. You can add it
$ yarn add qs
And then use it like that
import qs from 'qs'
const array = { a: { b: 'c' } }
const stringified = qs.stringify(array, { encode: false })
console.log(stringified) //-- outputs a[b]=c
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;
}
To do it in better way.
It can handle recursive objects or arrays in the STANDARD query form like a=val&b[0]=val&b[1]=val&c=val&d[some key]=val, here's the final function.
Logic, Functionality
const objectToQueryString = (initialObj) => {
const reducer = (obj, parentPrefix = null) => (prev, key) => {
const val = obj[key];
key = encodeURIComponent(key);
const prefix = parentPrefix ? `${parentPrefix}[${key}]` : key;
if (val == null || typeof val === 'function') {
prev.push(`${prefix}=`);
return prev;
}
if (['number', 'boolean', 'string'].includes(typeof val)) {
prev.push(`${prefix}=${encodeURIComponent(val)}`);
return prev;
}
prev.push(Object.keys(val).reduce(reducer(val, prefix), []).join('&'));
return prev;
};
return Object.keys(initialObj).reduce(reducer(initialObj), []).join('&');
};
Example
const testCase1 = {
name: 'Full Name',
age: 30
}
const testCase2 = {
name: 'Full Name',
age: 30,
children: [
{name: 'Child foo'},
{name: 'Foo again'}
],
wife: {
name: 'Very Difficult to say here'
}
}
console.log(objectToQueryString(testCase1));
console.log(objectToQueryString(testCase2));
Live Test
Expand the snippet below to verify the result in your browser -
const objectToQueryString = (initialObj) => {
const reducer = (obj, parentPrefix = null) => (prev, key) => {
const val = obj[key];
key = encodeURIComponent(key);
const prefix = parentPrefix ? `${parentPrefix}[${key}]` : key;
if (val == null || typeof val === 'function') {
prev.push(`${prefix}=`);
return prev;
}
if (['number', 'boolean', 'string'].includes(typeof val)) {
prev.push(`${prefix}=${encodeURIComponent(val)}`);
return prev;
}
prev.push(Object.keys(val).reduce(reducer(val, prefix), []).join('&'));
return prev;
};
return Object.keys(initialObj).reduce(reducer(initialObj), []).join('&');
};
const testCase1 = {
name: 'Full Name',
age: 30
}
const testCase2 = {
name: 'Full Name',
age: 30,
children: [
{name: 'Child foo'},
{name: 'Foo again'}
],
wife: {
name: 'Very Difficult to say here'
}
}
console.log(objectToQueryString(testCase1));
console.log(objectToQueryString(testCase2));Things to consider.
- It skips values for
functions,null,undefined - It skips
keysandvaluesfor empty objects and arrays. - It doesn't handle Number or String Objects made with
new Number(1)ornew String('my string')because NO ONE should ever do that
I've written a package just for that: object-query-string :)
Supports nested objects, arrays, custom encoding functions etc. Lightweight & jQuery free.
// TypeScript
import { queryString } from 'object-query-string';
// Node.js
const { queryString } = require("object-query-string");
const query = queryString({
filter: {
brands: ["Audi"],
models: ["A4", "A6", "A8"],
accidentFree: true
},
sort: 'mileage'
});
returns
filter[brands][]=Audi&filter[models][]=A4&filter[models][]=A6&filter[models][]=A8&filter[accidentFree]=true&sort=milage
After going through some top answers here, I have wrote another implementation that tackles some edge cases as well
function serialize(params, prefix) {
return Object.entries(params).reduce((acc, [key, value]) => {
// remove whitespace from both sides of the key before encoding
key = encodeURIComponent(key.trim());
if (params.constructor === Array ) {
key = `${prefix}[]`;
} else if (params.constructor === Object) {
key = (prefix ? `${prefix}[${key}]` : key);
}
/**
* - undefined and NaN values will be skipped automatically
* - value will be empty string for functions and null
* - nested arrays will be flattened
*/
if (value === null || typeof value === 'function') {
acc.push(`${key}=`);
} else if (typeof value === 'object') {
acc = acc.concat(serialize(value, key));
} else if(['number', 'boolean', 'string'].includes(typeof value) && value === value) { // self-check to avoid NaN
acc.push(`${key}=${encodeURIComponent(value)}`);
}
return acc;
}, []);
}
function objectToQueryString(queryParameters) {
return queryParameters ? serialize(queryParameters).join('&'): '';
}
let x = objectToQueryString({
foo: 'hello world',
bar: {
blah: 123,
list: [1, 2, 3],
'nested array': [[4,5],[6,7]] // will be flattened
},
page: 1,
limit: undefined, // field will be ignored
check: false,
max: NaN, // field will be ignored
prop: null,
' key value': 'with spaces' // space in key will be trimmed out
});
console.log(x); // foo=hello%20world&bar[blah]=123&bar[list][]=1&bar[list][]=2&bar[list][]=3&bar[nested%20array][][]=4&bar[nested%20array][][]=5&bar[nested%20array][][]=6&bar[nested%20array][][]=7&page=1&check=false&prop=&key%20value=with%20spaces
const objectToQueryParams = (o = {}) =>
Object.entries(o)
.map((p) => `${encodeURIComponent(p[0])}=${encodeURIComponent(p[1])}`)
.join("&");
Refer below gist for more: https://gist.github.com/bhaireshm
Typescript version for PHP notation (no url escaped version)
/**
* Converts an object into a Cookie-like string.
* @param toSerialize object or array to be serialized
* @param prefix used in deep objects to describe the final query parameter
* @returns ampersand separated key=value pairs
*
* Example:
* ```js
* serialize({hello:[{world: "nice"}]}); // outputs "hello[0][world]=nice"
* ```
* ---
* Adapted to TS from a StackOverflow answer https://stackoverflow.com/a/1714899/4537906
*/
const serialize = (toSerialize: unknown = {}, prefix?: string) => {
const keyValuePairs = [];
Object.keys(toSerialize).forEach((attribute) => {
if (Object.prototype.hasOwnProperty.call(toSerialize, attribute)) {
const key = prefix ? `${prefix}[${attribute}]` : attribute;
const value = toSerialize[attribute];
const toBePushed =
value !== null && typeof value === "object"
? serialize(value, key)
: `${key}=${value}`;
keyValuePairs.push(toBePushed);
}
});
return keyValuePairs.join("&");
};
Just use the following:
encodeURIComponent(JSON.stringify(obj))
// elastic search example
let story ={
"query": {
"bool": {
"must": [
{
"term": {
"revision.published": 0,
}
},
{
"term": {
"credits.properties.by.properties.name": "Michael Guild"
}
},
{
"nested": {
"path": "taxonomy.sections",
"query": {
"bool": {
"must": [
{
"term": {
"taxonomy.sections._id": "/science"
}
},
{
"term": {
"taxonomy.sections._website": "staging"
}
}
]
}
}
}
}
]
}
}
}
const whateva = encodeURIComponent(JSON.stringify(story))
console.log(whateva)const querystring= {};
querystring.stringify = function (obj, sep = '&', eq = '=') {
const escape = encodeURIComponent;
const qs = [];
let key = null;
for (key in obj) if (obj.hasOwnProperty(key)) {
qs.push(escape(key) + eq + escape(String(obj[key])));
}
return qs.join(sep);
};
Example:
const a = querystring.stringify({a: 'all of them', b: true});
console.log(a); // Output: a=all%20of%20them&b=true
here is a simple implementation that gets an object and converts it to query params string
export function objectToQueryParams(queryParams: object): string {
return queryParams ?
Object.entries(queryParams).reduce((acc, [key, val], index) => {
const sign = index === 0 ? '?' : '&';
acc += `${sign}${encodeURIComponent(key)}=${encodeURIComponent(val)}`;
return acc;
}, '')
: '';
}
My implementation of encoding object as query string, using reduce:
export const encodeAsQueryString = (params) => (
Object.keys(params).reduce((acc, key)=>(
params.hasOwnProperty(key) ? (
[...acc, encodeURIComponent(key) + '=' + encodeURIComponent(params[key])]
) : acc
), []).join('&')
);
If you want to pass an entire object as a single param, e.g ?filter={param1: "val1", param2: "val2"}
const serializeObject = (obj) => {
let objStr = JSON.stringify(obj);
objStr = objStr.replace(/\{/g, encodeURIComponent("{"));
objStr = objStr.replace(/}/g, encodeURIComponent("}"));
objStr = objStr.replace(/:/g, encodeURIComponent(":"));
return objStr;
};
let res = serializeObject({param1: "val1", param2: "val2"});
console.log("serializeObject:", res); //%7B"param1"%3A"val1","param2"%3A"val2"%7D
console.log("serializeObject-decoded:", decodeURIComponent(res)); //{"param1":"val1","param2":"val2"}
you can pass an object to this function with undefined properties, if the property exist will be converted to query string and the query string will be returned
function convertToQueryString(props) {
const objQueryString = { ...props };
for (const key in objQueryString) {
if (!key) {
delete objQueryString[key];
}
}
const params = JSON.stringify(objQueryString);
const qs = params
.replace(/[/''""{}]/g, '')
.replace(/[:]/g, '=')
.replace(/[,]/g, '&');
console.log(qs)
return qs;
}
convertToQueryString({order: undefined, limit: 5, page: 1})URLSearchParams looks good, but it didn't work for nested objects.
try to use
encodeURIComponent(JSON.stringify(object))
let data = {
id:1,
name:'Newuser'
};
const getqueryParam = data => {
let datasize = Object.keys(data).length;
let initial = '?';
Object.keys(data).map(function (key, index) {
initial = initial.concat(`${key}=${data[key]}`);
index != datasize - 1 && (initial = initial.concat('&'));
});
console.log(initial, 'MyqueryString');
return initial;
};
console.log(getqueryParam(data))//You can get the query string here
If you have baseUrl means to get full query use
baseUrl.concat(getqueryParam(data))
You can just encrypt the object after JSON.stringify() and send it as one parameter, then after receiving it, just decrypt it and cast it to object from string using JSON.parse()
You can also achieve this by using simple JavaScript.
const stringData = '?name=Nikhil&surname=Mahirrao&age=30';
const newData= {};
stringData.replace('?', '').split('&').map((value) => {
const temp = value.split('=');
newData[temp[0]] = temp[1];
});
console.log('stringData: '+stringData);
console.log('newData: ');
console.log(newData);const serialize = obj => Object.keys(obj).reduce((a, b) =>
a.push(encodeURIComponent(b) + "=" + encodeURIComponent(obj[b])) && a,
[]).join("&");
Call:
console.log(serialize({a:1,b:2}));
// output: 'a=1&b=2
'
Here is a simple answer that deals with strings and arrays at the same time during conversion.
jsonToQueryString: function (data) {
return Object.keys(data).map((key) => {
if (Array.isArray(data[key])) {
return (`${encodeURIComponent(key)}=${data[key].map((item) => encodeURIComponent(item)).join('%2C')}`);
}
return(`${encodeURIComponent(key)}=${encodeURIComponent(data[key])}`);
}).join('&');
}
While there are limits to query-string lengths that should be considered (for sending JSON data in HTTP/s GET calls versus using POST) ...
JSON.stringify(yourJSON) will create a String from your JSON object.
Then just hex-encode it (link below).
That will work ALWAYS versus various possible problems with base64 type URL encoding, UTF-8 characters, nested JSON objects and such.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify
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