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

Alanis Chua
Alanis Chua
2,830 Points
Posted by Alanis Chua
Alanis Chua
2,830 Points

ReferenceError: isNan is not defined

function randomNumber(lowerValue, upperValue){
  if( isNan(lowerValue) || isNaN(upperValue) ){
    throw new Error('error message');
} 
  return Math.floor(Math.random() * (upperValue - lowerValue + 1)) + lowerValue; 
};

console.log( randomNumber(2,33) );
console.log( randomNumber(2,"aa") );

why is there an error on second line?

Danny Percy
Danny Percy
3,719 Points
Danny Percy
Danny Percy
3,719 Points

And also make sure you delete that semicolon at the end of function :) Have a nice day!

3 Answers

Alfi Potter
Alfi Potter
7,248 Points
Alfi Potter
Alfi Potter
7,248 Points

Functions in Javascript are case sensitive, so isNan fails as the function is not defined whereas isNaN succeeds.

So like you did for the upperValue isNaN(upperValue) should be the same for isNaN(lowerValue)

nelson taj
PLUS
nelson taj
Courses Plus Student 3,869 Points
nelson taj
nelson taj
Courses Plus Student 3,869 Points

Here is the correct code below. You typed an small 'n' in the second line. good luck! N

function randomNumber(lowerValue, upperValue){ if( isNaN(lowerValue) || isNaN(upperValue) ){ throw new Error('error message'); }

Janet Leon
Janet Leon
6,908 Points
Janet Leon
Janet Leon
6,908 Points

I had the same problem. Thanks!