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JavaScript JavaScript Basics (Retired) Creating Reusable Code with Functions Random Number Challenge

Aaron Selonke
Aaron Selonke
10,323 Points
Posted by Aaron Selonke
Aaron Selonke
10,323 Points

Why is does the alert come back "undefined" with no error in the console?

function randomNumber(high, low) {
  Math.floor(Math.random() * (high - low)) + low; 
}

alert( randomNumber(6,1) );

2 Answers

Erwin Meesters
Erwin Meesters
15,088 Points
Erwin Meesters
Erwin Meesters
15,088 Points

Your function is indeed returning nothing. This will work:

function randomNumber(high, low) {
  return Math.floor(Math.random() * (high - low)) + low; 
}

alert( randomNumber(6,1) );
Gunhoo Yoon
Gunhoo Yoon
5,027 Points
Gunhoo Yoon
Gunhoo Yoon
5,027 Points

Because your function is not returning any value. The behaviour of JavaScript when return statement is not present in a function is to return value of undefined.