CODEWITHSUNDEEP
javascriptunderscore.jslodash
07_05_GuyT
07_05_GuyT

Reputation: 2887

Add new properties of object in lodash

I've two objects and I want to add properties from object A to object B and I try with extend which doesn't work,do I need to use something different ?

a = {
name = "value"
name2 = "value2"
}

b = {
name3 = "value"
name4 = "value2"
}

I want that A will contain both 

a = {
name = "value"
name2 = "value2"
name3 = "value"
name4 = "value2"
}

Upvotes: 21

Views: 63925

Answers (3)

T.J. Crowder
T.J. Crowder

Reputation: 1074989

_.extend (now called _.assign) is indeed how you do this:

_.assign(a, b);

Live Example:

const a = {
    name: "value",
    name2: "value2",
};

const b = {
    name3: "value",
    name4: "value2",
};

_.assign(a, b);
console.log(JSON.stringify(a, null, 2));
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.16.6/lodash.min.js"></script>

Though as of ES2015, you don't need Lodash for it, you can use the native Object.assign:

Live Example:

const a = {
    name: "value",
    name2: "value2",
};

const b = {
    name3: "value",
    name4: "value2",
};

Object.assign(a, b);
console.log(JSON.stringify(a, null, 2));
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.16.6/lodash.min.js"></script>

Upvotes: 43

Matthias A. Eckhart
Matthias A. Eckhart

Reputation: 5156

First of all, your defined objects are incorrect. Objects must be written as name:value pairs, separated by a colon (and not by an equality sign). Furthermore, you must use comma separators to delimit the properties of the object, like:

var person = {
    firstName: "Matthias",
    lastName: "Eckhart",
    eyeColor: "blue"
};

To extend an object with various properties via lodash, you can use _.assign(object, [sources], [customizer], [thisArg]):

var a = {
  name: "value",
  name2: "value2"
};

var b = {
  name3: "value",
  name4: "value2"
};

_.assign(a, b); // extend

console.log(a);
<script src="https://raw.githubusercontent.com/lodash/lodash/3.10.1/lodash.min.js"></script>

Upvotes: 7

jwkicklighter
jwkicklighter

Reputation: 126

I believe you want to use the lodash merge function, rather than extend. See: Lodash - difference between .extend() / .assign() and .merge()

Upvotes: 3

Related Questions