Javascript Replace keys within an array of objects

May 27, 2023

I have an array of objects as below

[
    {contactTypeField-0: 'Index0', firstNameField-0: '0', uniqueRowField-0: 0},
    {contactTypeField-1: 'Index1', firstNameField-1: '1', uniqueRowField-1: 0}
]

What is the best way to replace the keys i.e. I want to remove -0, -1, -2 from each of the keys. So I am expecting the output as

[
    {contactTypeField: 'Index0', firstNameField: '0', uniqueRowField: 0},
    {contactTypeField: 'Index1', firstNameField: '1', uniqueRowField: 0}
]

Is there some ES6 way to achieve this ?

>Solution :

You can use Array#map to transform the array of objects to a new array.

For each object, map over its entries and use String#replace to remove the required suffix (the regular expression -\d+$ matches a hyphen and one or more consecutive digits directly preceding the end of the string). Finally, use Object.fromEntries to convert the array of key-value pairs back to an object.

const arr=[{"contactTypeField-0":"Index0","firstNameField-0":"0","uniqueRowField-0":0},{"contactTypeField-1":"Index1","firstNameField-1":"1","uniqueRowField-1":0}];
const res = arr.map(o => Object.fromEntries(Object.entries(o)
                .map(([k, v]) => [k.replace(/-\d+$/, ''), v])));
console.log(res);