TypeScript accessing object though key variable error

Asked Jul 13 '21 at 13:57

Active Jul 13 '21 at 14:00

Viewed 57 times

I have an object which looks something like this

interface atype {
 A: number;
 B: number;
}


const a: atype = {
 A: 1,
 B: 2
}

I would like to access the value of a property of a depending on a given string with the key. i.e.

const val = a.[key]

this works but I get the error Identifier expected. now if I try doing

const val = a[key]

Now I get the error

Element implicitly has an 'any' type because expression of type 'string' can't be used to index type 'atype'.
No index signature with a parameter of type 'string' was found on type 'atype'.

Could someone help me figure out how to do this w/o any errors/warnings

edited Jul 13 '21 at 14:00

Heretic Monkey

11,687
7
53
122

asked Jul 13 '21 at 13:57

user15032172

where is the declaration of key? Please share the function in which you are using `key` – Amir Saleem Jul 13 '21 at 13:59
so I am using a for loop which goes through an array of strings where these strings are the key, so the key is a string – user15032172 Jul 13 '21 at 14:00
please add that loop code as well – Amir Saleem Jul 13 '21 at 14:01
If you type the key as `keyof atype`, it won't throw the errors. – Heretic Monkey Jul 13 '21 at 14:01

TypeScript accessing object though key variable error

0 Answers0