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JavaScript JavaScript Basics (Retired) Working With Numbers The Random Challenge

Sam Sammut
Sam Sammut
1,616 Points
Posted by Sam Sammut
Sam Sammut
1,616 Points

Why would you use parseInt in this code challenge?

So this is my code, why would you use parseInt in this coding challenge? I've seen it used in several examples in the Q&A section. Thank in advance ?.

var userNum = prompt('Please select a number');
console.log(userNum);
var randomNumber = Math.floor( Math.random() * (userNum)) +1;
alert(randomNumber);

1 Answer

Martin Zarate
Martin Zarate
10,723 Points

For data validation. Even if the data coming in is a number, it is a good practice to use parseInt() when dealing with external data included into your code. If the input comes from the prompt() then the parseInt() is a must, since all data coming in from prompt() is of string type. Cheers.

Sam Sammut
Sam Sammut
1,616 Points
Sam Sammut
Sam Sammut
1,616 Points

Thanks so much for clearing this up. I've never programmed with JavaScript before so any explanations I get will be insightful. Cheers again!