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30-seconds-of-code/snippets/validate-number.md
2017-12-14 00:17:19 -08:00

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### Validate number
Use `!isNaN` in combination with `parseFloat()` to check if the argument is a number.
Use `isFinite()` to check if the number is finite.
Use `Number()` to check if the coercion holds.
```js
const validateNumber = n => !isNaN(parseFloat(n)) && isFinite(n) && Number(n) == n;
// validateNumber('10') -> true
```