Rename Key in JS Object with values from another array

Question

I want to rename the keys in the object with the names of the array

let title = [
    'Total Cryptocurrencies',
    'Total Markets',
    'Total Exchanges',
    'Total Market Cap',
    'Total 24h Volume', 
];

var obj = {
    1: 5,
    2: 7,
    3: 0,
    4: 0,
    5: 0,
};

So in the end I want to have my object like this:

var obj = {
    'Total Cryptocurrencies': 5,
    'Total Markets': 7,
    'Total Exchanges': 0,
    'Total Market Cap': 0,
    'Total 24h Volume': 0,
};

Does this answer your question? [JavaScript: Object Rename Key](https://stackoverflow.com/questions/4647817/javascript-object-rename-key) — codingmaster398, Mar 08 '22 at 11:22
Also, you can't guarantee the sort order of object properties when you iterate over them, so how would you know which array element matches the right object key? — Andy, Mar 08 '22 at 11:23
[How much research effort is expected of Stack Overflow users?](https://meta.stackoverflow.com/questions/261592/how-much-research-effort-is-expected-of-stack-overflow-users) — Andreas, Mar 08 '22 at 11:24
The code is only putting "" on the key and not renaming it with the names of the array — David, Mar 08 '22 at 11:32

score 0 · Accepted Answer · answered Mar 08 '22 at 11:29

You could do it with a for loop as follows.

let title = [
    'Total Cryptocurrencies',
    'Total Markets',
    'Total Exchanges',
    'Total Market Cap',
    'Total 24h Volume', 
];

var obj = {
    1: 5,
    2: 7,
    3: 0,
    4: 0,
    5: 0,
};

var newObj = {};

for(i = 0; i < title.length; i++) {
    newObj[title[i]] = obj[(i+1).toString()];
}

var obj = newObj;

Sandeep Ranjan · Answer 2 · 2022-03-08T14:20:19.220

-2

Not sure if it the best solution but you can try

obj= title.reduce((prev, curr, idx) => {return {...prev, [curr]: obj[idx+1]} }, {});

Assuming obj's keys will be numbers will map perfectly with the title indexes

edited Mar 08 '22 at 14:20

answered Mar 08 '22 at 11:28

Sandeep Ranjan

41
5

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Rename Key in JS Object with values from another array

2 Answers2