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JavaScript JavaScript Foundations Functions Return Values

Stephen Bicker
Stephen Bicker
3,686 Points
Posted by Stephen Bicker
Stephen Bicker
3,686 Points

Checking for 'undefined'

The project checker keeps telling me to check for 'undefined', yet I am doing just that. What am I missing?

Jason Anello
Jason Anello
Courses Plus Student 94,610 Points

Hi Stephen,

Post what code you have so far so you can get help with what you need to fix.

1 Answer

Jimmy Hsu
Jimmy Hsu
6,511 Points
Jimmy Hsu
Jimmy Hsu
6,511 Points

All you need to do is check for the type with an if loop with 'typeof', then name of your parameter, then is equal to signs. There's multiple ways to do this, but it appears this is how they want you to do it.

Below is one solution.

function arrayCounter (array) {
  if (typeof array === 'undefined' ||typeof array === 'string'||typeof array === 'number') {
    return 0; 
  }
  return array.length;
}