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JavaScript

Marco Fernandes
Marco Fernandes
663 Points
Posted by Marco Fernandes
Marco Fernandes
663 Points

Returning var instead of function

In the code below I would like the alert box to display a random number. But it only works when I type alert ( getRandomNumber); . Why is that it won't work if I type alert (randomNumber); ? For me, it makes sense to type alert (randomNumber); because this is the returned value.

Can someone break it down for me why it is incorrect?

Thanks.

function getRandomNumber() { var randomNumber = Math.floor( Math.random() * 6 ) + 1; return randomNumber; }

alert(getRandomNumber);

1 Answer

Steven Parker
Steven Parker
228,094 Points
Steven Parker
Steven Parker
228,094 Points

The variable named "randomNumber" only exists inside the function. Only the value is returned to the code where the function is invoked.

I also wouldn't expect "getRandomNumber" to work by itself — when you invoke ("call") a function, you must include parentheses after the name. But this should work:

alert(getRandomNumber());  // invoke "getRandomNumber" and display the result