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

R R
R R
1,570 Points
Posted by R R
R R
1,570 Points

Why am I getting the error "isNan is not defined"?

The code below generates the error message: Uncaught referenceError: isNan is not defined. Could someone tell me why, please?

function randomNumber(lower, upper) {

    if (isNan(lower) || isNan(upper)) {
     throw new Error("Both arguments must be numbers");
 }

return Math.floor(Math.random() * (upper - lower + 1)) + lower;
}

alert(randomNumber(1,100));

2 Answers

John Magee
John Magee
Courses Plus Student 9,058 Points

Javascript is case sensitive

isNaN, not isNan

R R
R R
1,570 Points
R R
R R
1,570 Points

oh geez. Should have caught that. Thank you.