Merge Two Javascript Objects If Key Is Equal With Either Lodash, Vanilla Js, Or D3

I have 3 similar javascript objects. var gdp = { 'city': city, 'gdp': [], }; var income = { 'city': city, 'income': [], }; var uRate = { 'city': city,

Solution 1:

To anyone landing here from Google, it's now pretty easy to do this with vanilla JS using Object.assign().

This is a zero-dependency equivalent to the result in the accepted answer:

Object.assign({}, gdp, income, uRate);

Note that this won't work in IE, but will work in Edge. The polyfill isn't too heavy, though.

Working solution at https://jsfiddle.net/bLhk6x6a/1/

Solution 2:

Using lodash _.merge will satisfy the original question:

Given 3 objects:

var gdp = {
    "city": city,
    "gdp": [],  
};

var income = {
    "city": city,
    "income": [],  
};

var uRate = {
    "city": city,
    "uRate": [],  
};

Then bring in lodash and do:

var finalData = _.merge(gdp, income, uRate);

and the result is as desired:

{
    "city": city, 
    "gdp": [],
    "income": [],
    "uRate": [] 
}

Working solution here: http://jsfiddle.net/e99KQ/3/