check if string is digit js 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: js check if string is integer
function isInt(str) {
return !isNaN(str) && Number.isInteger(parseFloat(str));
}