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JavaScript JavaScript Foundations Functions Return Values

Posted by Jacinda Zhong
Jacinda Zhong
3,695 Points

|| or boolean in if statements

In the challenge, I am trying to condense my if statements into 1, instead of using multiple else if's that do the same thing.

This doesn't work...why?

      function arrayCounter (array1) {
        if (typeof array1 === ('string' || 'number' || 'undefined')) {
          return 0;
        } else {
          return array1.length;
        }
      }

But this works, but it seems redundant with all the else if's that do practically the same thing.

function arrayCounter (array1) {
        if (typeof array1 === 'undefined') {
          return 0;
        } else if (typeof array1 === 'string') {
          return 0;
        } else if (typeof array1 === 'number') {
          return 0;
        } else {
          return array1.length;
        }
      }

1 Answer

Adam Sackfield
Adam Sackfield
Courses Plus Student 19,663 Points

Here is a simplified version to show how to use the || (or operator)

    function arrayCounter(a) { 
        if (typeof a === "number" || typeof a === "undefined" ) { 
            console.log(0);
        } else { 
            console.log(a.length); 
        } 
    }

       arrayCounter(25);
       arrayCounter("adam");

So to be clear you need to use the typeof each time. Just copy this into an html page and fire it up in a browser and view the console output for each time the function is called

Jacinda Zhong
Jacinda Zhong
3,695 Points

Ah, I see. I didn't realize that typeof had to be repeated. Thank you!

Adam Sackfield
Adam Sackfield
Courses Plus Student 19,663 Points

Your welcome!