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I'm trying to iterate over this enum. However I'm facing issues with extracting values from the enum. I can extract the value if i give it a hardcoded string like this.

export enum Values {
  ACE = 'A',
  TWO = '2',
  THREE = '3',
  FOUR = '4',
  FIVE = '5',
  SIX = '6',
  SEVEN = '7',
  EIGHT = '8',
  NINE = '9',
  TEN = '10',
  JACK = 'J',
  QUEEN = 'Q',
  KING = 'K',
}

console.log(Values['TWO']);

But as soon as i give it the multiple string values from the enum like below.

export enum Values {
  ACE = 'A',
  TWO = '2',
  THREE = '3',
  FOUR = '4',
  FIVE = '5',
  SIX = '6',
  SEVEN = '7',
  EIGHT = '8',
  NINE = '9',
  TEN = '10',
  JACK = 'J',
  QUEEN = 'Q',
  KING = 'K',
}

for (let value in Values) {
  console.log(Values[value]);
}

It gives the following error:

error TS7053: Element implicitly has an 'any' type because expression of type 'string' can't be used to index type 'typeof Values'.
  No index signature with a parameter of type 'string' was found on type 'typeof Values'.

25   console.log(Values[value]);

Completely new to TypeScript so might be missing something.

Cheers to anyone who could give me some guidance.

I'm trying to iterate over this enum. However I'm facing issues with extracting values from the enum. I can extract the value if i give it a hardcoded string like this.

export enum Values {
  ACE = 'A',
  TWO = '2',
  THREE = '3',
  FOUR = '4',
  FIVE = '5',
  SIX = '6',
  SEVEN = '7',
  EIGHT = '8',
  NINE = '9',
  TEN = '10',
  JACK = 'J',
  QUEEN = 'Q',
  KING = 'K',
}

console.log(Values['TWO']);

But as soon as i give it the multiple string values from the enum like below.

export enum Values {
  ACE = 'A',
  TWO = '2',
  THREE = '3',
  FOUR = '4',
  FIVE = '5',
  SIX = '6',
  SEVEN = '7',
  EIGHT = '8',
  NINE = '9',
  TEN = '10',
  JACK = 'J',
  QUEEN = 'Q',
  KING = 'K',
}

for (let value in Values) {
  console.log(Values[value]);
}

It gives the following error:

error TS7053: Element implicitly has an 'any' type because expression of type 'string' can't be used to index type 'typeof Values'.
  No index signature with a parameter of type 'string' was found on type 'typeof Values'.

25   console.log(Values[value]);

Completely new to TypeScript so might be missing something.

Cheers to anyone who could give me some guidance.

• javascript
• typescript
• loops
• enums

Share Improve this question Follow edited Jun 19, 2021 at 11:48 ToxicTuring asked Jun 19, 2021 at 11:41 ToxicTuringToxicTuring 9911 silver badge88 bronze badges 1

• 1 codesandbox.io/s/fancy-star-hlg2f?file=/src/App.tsx – Sarun UK Commented Jun 19, 2021 at 11:48

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1 Answer 1

Sorted by: Reset to default 9

The type of the loop variable while iterating using for-in loop over enum Values is implicitly any, so you get the pile error.

for (let value in Values) {
  console.log(Values[value]);
}

The variable value is of type any, which cannot be used to index the enum Values.

Open issue in TypeScript here.

If you want to iterate over the key-value pairs of the enum you can do so with the help of Object.entries:

enum Values {
  ACE = 'A',
  TWO = '2',
  THREE = '3',
  FOUR = '4',
  FIVE = '5',
  SIX = '6',
  SEVEN = '7',
  EIGHT = '8',
  NINE = '9',
  TEN = '10',
  JACK = 'J',
  QUEEN = 'Q',
  KING = 'K',
}

//Both key and value
Object.entries(Values).forEach(([key, value]) => {
    console.log(key, value)
});

//keys
Object.keys(Values).forEach(key => {
    console.log(key);
});

//values
Object.values(Values).forEach(value => {
    console.log(value);
});

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