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JavaScript JavaScript Numbers The Math Object Random Number Challenge – Solution

Posted by Caroline Louw
Caroline Louw
12,155 Points

How does the program know that the highNumber variable is a number and execute the first if statement?

And if not the else statement is executed?

4 Answers

Steve Fau
Steve Fau
5,622 Points

Hey Caloline,

This got me for a sec too, but here's the solution:

Before he goes to the if statement, he's parsing the number from the user input via the parseInt() method.

The user either enters something that can be parsed into a number, or the parseInt() method returns NaN, which then evaluates to false.

Read more about why NaN evaluates to false and other falsy values here: https://developer.mozilla.org/en-US/docs/Glossary/Falsy

Caroline Louw
Caroline Louw
12,155 Points

thanks

Diego Alvarez
Diego Alvarez
6,680 Points
Diego Alvarez
Diego Alvarez
6,680 Points

With the parseInt() method.

Caroline Louw
Caroline Louw
12,155 Points

thanks

Skyler Harris
Skyler Harris
7,670 Points
Skyler Harris
Skyler Harris
7,670 Points

Nice answer Steve that made a lot of sense!

Georgia Lloyd
Georgia Lloyd
3,384 Points
Georgia Lloyd
Georgia Lloyd
3,384 Points

Thanks, I was also wondering this