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JavaScript JavaScript Basics (Retired) Creating Reusable Code with Functions Random Number Challenge, Part II Solution

Mariano Okpalefe
Mariano Okpalefe
4,182 Points
Posted by Mariano Okpalefe
Mariano Okpalefe
4,182 Points

what's wrong with my code? it says that on line 4 error is undefined. Is it the order in which i showed my code or what?

function getRandomNumber( lower, upper ) {
  var randomNumberGen = Math.floor(Math.random() * ( upper - lower + 1)) + lower; 
  if ( lower || upper ) {
    throw new error("You have to type in a number, not a string you idiot!");
  } else {
      return randomNumberGen;
  }
}

console.log( getRandomNumber( 1, 100 ) );
console.log( getRandomNumber( 200, 'five hundred' ) );
console.log( getRandomNumber( 1000, 20000 ) );
console.log( getRandomNumber( 50, 100 ) );
Jesus Mendoza
Jesus Mendoza
23,289 Points
Jesus Mendoza
Jesus Mendoza
23,289 Points

In your code you're basically saying "If lower or upper exist then throw an error". It should be (!lower || !upper). Also it should be new Error, with capitalized E

3 Answers

Maximiliane Quel
PLUS
Maximiliane Quel
Courses Plus Student 55,489 Points
Maximiliane Quel
Maximiliane Quel
Courses Plus Student 55,489 Points

You need to adapt the condition in your if statement to test that whatever the person enters is only a number. Error is also a constructor that allows you to create an object so it is written with a capital letter at the beginning:

function getRandomNumber( lower, upper ) {
  if(isNaN(lower) || isNaN(upper)){
    throw new Error('You can only enter number into this function');
  } else {
    return Math.floor(Math.random() * (upper - lower + 1)) + lower;
  } 
}
Erik Nuber
Erik Nuber
20,629 Points
Erik Nuber
Erik Nuber
20,629 Points 
function getRandomNumber( lower, upper ) { 
var randomNumberGen = Math.floor(Math.random() * ( upper - lower + 1)) + lower; 
if ( isNaN( lower ) || isNaN(upper) ) { 
try  {
throw new Error("You have to type in a number, not a string you idiot!") 
 } catch (e) {
  console.log(e); 
} 
}else { 
return randomNumberGen; 
} 
}

console.log( getRandomNumber( 1, 100 ) ); 
console.log( getRandomNumber( 200, 'five hundred' ) ); 
console.log( getRandomNumber( 1000, 20000 ) ); 
console.log( getRandomNumber( 50, 100 ) );

Need a bit of extra coding. Your conditional statement needs to check if it is a number or not.

When you throw an error, Error is capitalized and, when it is thrown, you need to catch it as well. You can do anything with the catch, you can display it to the console, write it to the page etc.

Mariano Okpalefe
Mariano Okpalefe
4,182 Points
Mariano Okpalefe
Mariano Okpalefe
4,182 Points

thanks you guys i just misunderstood completely what i was supposed to be doing, I understand now