javascript check if value is number or string code example
Example 1: javascript check if string is number
// native returns true if the variable does NOT contain a valid number
isNaN(num)
// can be wrapped for making simple and readable
function isNumeric(num){
return !isNaN(num)
}
isNumeric(123) // true
isNumeric('123') // true
isNumeric('1e10000') // true (This translates to Infinity, which is a number)
isNumeric('foo') // false
isNumeric('10px') // false
Example 2: To check if a value is a number in JavaScript
const value = 2
isNaN(value) //false
isNaN('test') //true
isNaN({}) //true
isNaN(1.2) //false