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JavaScript JavaScript Foundations Functions Return Values

Nazaam Kutisha
Nazaam Kutisha
7,667 Points
Posted by Nazaam Kutisha
Nazaam Kutisha
7,667 Points

help me with this challenge.

Around line 17, 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.

I was thrown by the task of embedding an array into a function, and passing values of 'string' or 'number'

( "The function named 'arrayCounter' that takes in a parameter which is an array") ??? Im not sure of what he means here.

My best shot at this was.

<h1>JavaScript Foundations</h1>
    <h2>Functions: Return Values</h2>
    <script>

      function arrayCounter (string, number) {
        if (typeof number === 'undefined'){
          number = '0';
        }
        //console.log(greeting + "world! " + name);
        return string.length;

      }



    </script>

Many Thanks, Nazaam

2 Answers

Dino Paškvan
Dino Paškvan
Courses Plus Student 44,108 Points

Your function should accept only one parameter — an array. Of course, in JavaScript, you can't dictate what type a function accepts, so you check what it is, and depending on the result of that check, you do different things. In this case, you check if it really is an array. If it is, you return the length of the array. If it's not, you return 0.

function arrayCounter(array) { // take one parameter, let's call it array
   if (typeof array === "string" || typeof array === "number" || typeof array === "undefined") { // check if it's a string or a number or undefined
      return 0; // if it is, return 0, and the function stops executing here 
   } // if it's not, the code inside the if won't execute
   return array.length; // return the length of the array
}