How to map key value pairs of a map in JavaScript?

Question

Below is the map key/value pair I’ve in the JavaScript “map”:

var map = {"a": 1, "b": 2, "c": 3};

alert(JSON.stringify(map));

I want to get an mapper which contains key/value pair on each iteration like below: 

// ["a_1", "b_2", "c_3"]

map.map((key, value) => key + "_" + value);

Can anyone tell me how to do it?

 

Answer 1

You can use Object.entries to map on the key value pair like below:  

const map = {"a": 1, "b": 2, "c": 3};

const mapped = Object.entries(map).map(([k,v]) => `${k}_${v}`);

console.log(mapped);

Object.entries gives the following output: 

[

  [ "a", 1 ],

  [ "b", 2 ],

  [ "c", 3 ]

]

To create the String with template literals, you have to loop through every inner array. 

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