Check if a variable contains a numerical value in Javascript?

Question

In PHP, it\'s pretty easy:

is_numeric(23);//true
is_numeric(\"23\");//true
is_numeric(23.5);//true
is_numeric(true);//false

But how do I do

Answer 1

Here is my Solution : ES6/2015

Disclaimer: This solution works only if user send a Number Type as an input. For Example: 23 is a number type but '23' is not a number type it is a String Type.

function isValidNumber(value) {
  return typeof value === 'number' && Number.isNaN(value) === false;
}

Test Cases

isValidNumber(10) // true
isValidNumber(10.34) // true
isValidNumber('geo10') // false
isValidNumber('10geo') // false
isValidNumber('') // false
isValidNumber(NaN) // false
isValidNumber(true) // false
isValidNumber(false) // false