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JavaScript

Kathryn Kassapides
Kathryn Kassapides
9,260 Points
Posted by Kathryn Kassapides
Kathryn Kassapides
9,260 Points

Why exactly do you have to change 'Mercury' to 'MERCURY' after you place the .toUpperCase?

And how does it know that any the answer 'mercury' typed anyway is correct? For example, MerCurY or mercury or MERCURy? if (answer.toUpperCase() === 'MERCURY'() { console.log (Sorry, your incorrect); }

1 Answer

Ave Nurme
Ave Nurme
20,907 Points
Ave Nurme
Ave Nurme
20,907 Points

Hi Kathryn

In this example we convert the user input to all uppercase letters so that we could compare it with the word 'MERCURY' which is the correct answer. We do not know upfront what the user will give us as an input. The user can even give us 'Mercury' or 'mercury' or 'MERCURY', too. I am new to JavaScript and just learning myself but I don't think the program itself really cares about 'Mercury' or 'mercury' or 'MERCURY' - it will transform the string to uppercase anyway and make the comparison.

In order to evalute this condition if (answer.toUpperCase() === 'MERCURY') to true the user input must match with the answer (in this case 'MERCURY').

So the short answer is that we need to test if a response is correct and we can do this with the toUpperCase()-method.

I hope this makes sense!