How get only number data type as parameter in function Javascript

Question

oddeven("asd") output keep showing asd is odd. How to make it show asd is not a number?

   let num;

    function oddeven(num){
        num = parseInt(num);

        if(num%2 == 0){
            document.write(num + " is even" + "<br>");
        }else if(num%2 != 0){
            document.write(num + " is odd" + "<br>")
        }else
            document.write(num + " is not a number" + "<br>");
    }
    oddeven(2);
    oddeven(1);
    oddeven(10);
    oddeven(7);
    oddeven("asd");

Answer 1

You can modify your function to check for non-numbers like this:

function oddeven(num) {
    if (isNaN(num)) {
        document.write(num + " is not a number" + "<br>");
    } else {
        num = parseInt(num);
        if (num % 2 == 0) {
        document.write(num + " is even" + "<br>");
        } else {
        document.write(num + " is odd" + "<br>")
        }
    }
}

UPDATE problem in your code: in the case of oddeven("asd"), your variable num was being set as NaN so your second test was passing.