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JavaScript JavaScript Basics (Retired) Creating Reusable Code with Functions Random Number Challenge, Part II Solution

isNaN is not defined

I'm trying to test my code to ensure I get my custom error message when entering a string as an argument for the randomNumber function. However, when I check the console, I keep getting an error stating isNaN is not defined. Can someone tell me why this is and how I can resolve this?

function randomNumber(upper, lower){
  if(isNan(upper) || isNaN(lower)){
   throw new Error('Both arguments must be numbers');
  }else{
  return Math.floor(Math.random() * (upper - lower + 1)) + lower; 
  }
}
alert(randomNumber("ten", 6));
alert(randomNumber(13, 9));
alert(randomNumber(100, 1));

1 Answer

You have a typo for your first "isNaN". You wrote, "isNan".

I knew it had to be something tiny I was overlooking. THANK YOU