Removing first character of each value in a object

Question

What I have is:

routeLinks = {
    Store: '/store',
    Department: '/department',
    Home: '/home'
}

What I want is:

routeLinks = {
    Store: 'store',
    Department: 'department',
    Home: 'home'
}

i.e. modified object values with first character removed

score 4 · Answer 1 · answered Jul 02 '19 at 05:43

4

Use slice:

const routeLinks = { Store: '/store', Department: '/department', Home: '/home' };

const res = Object.entries(routeLinks).reduce((a, [k, v]) => (a[k] = v.slice(1), a), {});

console.log(res);

Or just use for...in:

const routeLinks = { Store: '/store', Department: '/department', Home: '/home' };

for (let k in routeLinks) {
  routeLinks[k] = routeLinks[k].slice(1);
}

console.log(routeLinks);

answered Jul 02 '19 at 05:43

Jack Bashford

43,180
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50
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I am getting an error with first solution: Property 'entries' does not exist on type 'ObjectConstructor'. – Ashish Kumar Jul 02 '19 at 05:46
What environment are you using? TypeScript? Node? – Jack Bashford Jul 02 '19 at 05:47
I am using typescript – Ashish Kumar Jul 02 '19 at 05:51
1

See [here](https://stackoverflow.com/q/45422573/10221765) on how to fix that. – Jack Bashford Jul 02 '19 at 05:52

Mamun · Answer 2 · 2019-07-02T06:00:01.283

2

You can loop through the object with for...in loop and substring the value:

var routeLinks = {
  Store: '/store',
  Department: '/department',
  Home: '/home'
}
for(var k in routeLinks){
  routeLinks[k] = routeLinks[k].substring(1);
}
console.log(routeLinks);

Update: Solution using forEach() and arrow function (=>)

var routeLinks = {
  Store: '/store',
  Department: '/department',
  Home: '/home'
};
Object.keys(routeLinks).forEach(k => routeLinks[k] = routeLinks[k].substring(1));
console.log(routeLinks);

edited Jul 02 '19 at 06:00

answered Jul 02 '19 at 05:46

Mamun

66,969
9
47
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Could you suggest a solution using lambda expression rather than for loop? – Ashish Kumar Jul 02 '19 at 05:50
1

@AshishKumar, please see the second answer:) – Mamun Jul 02 '19 at 06:00

score 1 · Answer 3 · answered Jul 02 '19 at 05:51

Here is a functional version that doesn't mutate the input

routeLinks = {
    Store: '/store',
    Department: '/department',
    Home: '/home'
};

const trimStart = obj => Object.keys(obj).reduce((result, key) => ({...result, [key]: obj[key].substr(1) }), {});

console.log(trimStart(routeLinks));

Removing first character of each value in a object

3 Answers3