Concatenate two JSON objects

Question

I have two JSON objects with the same structure and I want to concat them together using Javascript. Is there an easy way to do this?

Answer 1

If you'd rather copy the properties:

var json1 = { value1: '1', value2: '2' };
var json2 = { value2: '4', value3: '3' };


function jsonConcat(o1, o2) {
 for (var key in o2) {
  o1[key] = o2[key];
 }
 return o1;
}

var output = {};
output = jsonConcat(output, json1);
output = jsonConcat(output, json2);

Output of above code is{ value1: '1', value2: '4', value3: '3' }

Answer 2

The actual way is using JS Object.assign.

Object.assign(target, ...sources)

MDN Link

There is another object spread operator which is proposed for ES7 and can be used with Babel plugins.

 Obj = {...sourceObj1, ...sourceObj2}

Answer 3

I use:

let x = { a: 1, b: 2, c: 3 }

let y = {c: 4, d: 5, e: 6 }

let z = Object.assign(x, y)

console.log(z)

// OUTPUTS:
{ a:1, b:2, c:4, d:5, e:6 }

From here.

Answer 4

You can use jquery extend method.

Example:

o1 = {"foo":"bar", "data":{"id":"1"}};
o2 = {"x":"y"};
sum = $.extend(o1, o2);

Result:

sum = {"foo":"bar", "data":{"id":"1"}, "x":"y"}

Answer 5

One solution is to use a list/array:

var first_json = {"name":"joe", "age":27};
var second_json = {"name":"james", "age":32};

var jsons = new Array();
jsons.push(first_json);
jsons.push(second_json);

Result

jsons = [
    {"name":"joe", "age":27},
    {"name":"james", "age":32}
]

Answer 6

if using TypeScript, you can use the spread operator (...)

var json = {...json1,...json2} 

Answer 7

You can use Object.assign() method. The Object.assign() method is used to copy the values of all enumerable own properties from one or more source objects to a target object. It will return the target object.[1]

var o1 = { a: 1 }, o2 = { b: 2 }, o3 = { c: 3 };

var obj = Object.assign(o1, o2, o3);
console.log(obj); // { a: 1, b: 2, c: 3 }

Answer 8

okay, you can do this in one line of code. you'll need json2.js for this (you probably already have.). the two json objects here are unparsed strings.

json1 = '[{"foo":"bar"},{"bar":"foo"},{"name":"craig"}]';

json2 = '[{"foo":"baz"},{"bar":"fob"},{"name":"george"}]';

concattedjson = JSON.stringify(JSON.parse(json1).concat(JSON.parse(json2)));

Answer 9

Just try this, using underscore

var json1 = [{ value1: '1', value2: '2' },{ value1: '3', value2: '4' }];
var json2 = [{ value3: 'a', value4: 'b' },{ value3: 'c', value4: 'd' }];
var resultArray = [];
json1.forEach(function(obj, index){
  resultArray.push(_.extend(obj,  json2[index]));
});

console.log("Result Array", resultArray);

Result

Answer 10

var baseArrayOfJsonObjects = [{},{}];
for (var i=0; i<arrayOfJsonObjectsFromAjax.length; i++) {
    baseArrayOfJsonObjects.push(arrayOfJsonObjectsFromAjax[i]);
}

Answer 11

I use:

let jsonFile = {};    
let schemaJson = {};    
schemaJson["properties"] = {};    
schemaJson["properties"]["key"] = "value";
jsonFile.concat(schemaJson);

Answer 12

The simplest way :

const json1 = { value1: '1', value2: '2' };
const json2 = { value2: '4', value3: '3' };

const combinedData = {
  json1,
  json2
};

console.log(combinedData)