javascriptnumbersdigits

Check if string contains only digits

I want to check if a string contains only digits. I used this:

var isANumber = isNaN(theValue) === false;

if (isANumber){
    ..
}

But realized that it also allows + and -. Basically, I want to make sure an input contains ONLY digits and no other characters. Since +100 and -5 are both numbers, isNaN() is not the right way to go. Perhaps a regexp is what I need? Any tips?

Solution

  • how about

    let isnum = /^\d+$/.test(val);