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JavaScript JavaScript Foundations Functions Return Values

Pierre Ramirez
Pierre Ramirez
5,632 Points
Posted by Pierre Ramirez
Pierre Ramirez
5,632 Points

Having issues with this function returning a zero

So in this function I have an if statement where if it's blank then it shows zero and if it's not it shows length. Am I doing something wrong here?

  function arrayCounter(arg1){
    if(typeof arg1 === 'undefined'){
      return 0;
    }else{
      return arg1.length;
    }
  }
arrayCounter();
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(arg1){
        if(typeof arg1 === 'undefined'){
          return 0;
        }else{
          return arg1.length;
        }
      }
    arrayCounter();
    </script>


  </body>
</html>

1 Answer

Marcus Parsons
Marcus Parsons
15,719 Points
Marcus Parsons
Marcus Parsons
15,719 Points

Hey Pierre Ramirez,

You have to check for more than just undefined in your if statement. You need to also check for a string or number so your if statement needs to be expanded like so:

  function arrayCounter(arg1){
      //Check to see if arg1 is undefined, string, or number
        if(typeof arg1 === 'undefined' || typeof arg1 === 'string' || typeof arg1 === 'number'){
          return 0;
        }else{
          return arg1.length;
        }
      }
    arrayCounter();