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

Posted by Jules Al
Jules Al
1,096 Points

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

Allison Walker
Allison Walker
17,137 Points

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

Jules Al
Jules Al
1,096 Points

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