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JavaScript JavaScript Foundations Functions Return Values

Posted by Ahmad Almoghraby
Ahmad Almoghraby
6,769 Points

Functions , Returns

I would Really Appreciate it if someone can answer this question! create a function named 'arrayCounter' that takes in a parameter which is an array. The function must return the length of an array passed in or 0 if a 'string', 'number' or 'undefined' value is passed in.

index.html 
<!DOCTYPE html>
<html lang="en">
  <head>
    <title>JavaScript Foundations: Functions</title>
    <style>
      html {
        background: #FAFAFA;
        font-family: sans-serif;
      }
    </style>
  </head>
  <body>
    <h1>JavaScript Foundations</h1>
    <h2>Functions: Return Values</h2>
    <script>
      function arrayCounter (num) {
        if (num == 'undefined') {
          return num.length;
        }
        return 0;
      }

      console.log(arrayCounter());
    </script>
  </body>
</html>

2 Answers

Richard Barkinskiy
Richard Barkinskiy
10,663 Points

You will need to test to see if the parameter (array) is either undefined, string, or number and if it is, return "0" otherwise return the length of the parameter (array).

Here's my code as an example:

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

Good luck!

Ahmad Almoghraby
Ahmad Almoghraby
6,769 Points

There was an error in your code .(it said) :/

Hugo Paz
Hugo Paz
15,622 Points

Ahmad, Richard solution works. Did you put it inside the script tags?

Ahmad Almoghraby
Ahmad Almoghraby
6,769 Points

This is how I did it:

<script> function arrayCounter (x) { if (x === 'undefined' || x === 'strings' || x === 'numbers') { return 0; } else { return x.length; } }

console.log(arrayCounter()); </script>

If it is still wrong Please let me know !

Hugo Paz
Hugo Paz
15,622 Points

Ahmad you forgot to put "typeof" before each check.

if(typeof x === "undefined" || typeof x === "string" || typeof x === "number")
Ahmad Almoghraby
Ahmad Almoghraby
6,769 Points

what does typeof do ?

Hugo Paz
Hugo Paz
15,622 Points

It checks the type of the element.

Ahmad Almoghraby
Ahmad Almoghraby
6,769 Points
Ahmad Almoghraby
Ahmad Almoghraby
6,769 Points

Ok, I'll see what will happen. Thank You so much :)