How do I pass an array into a function parameter?

Question

I've been trying this challenge over and over again, and I'm trying to figure out how to pass an array as a function parameter, and then call the array inside the function.

Please Help!

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    <title>JavaScript Foundations: Functions</title>
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    <h1>JavaScript Foundations</h1>
    <h2>Functions: Return Values</h2>
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Answer 1 · 2015-02-15T02:32:22Z

February 15, 2015 2:32am

Hey Paul Hubbard,

When you're passing in arguments to a function, an argument can be pretty much anything. It can be a string, number, object/array, another function, etc. When it tells you that you're passing in an array, it is more to let you know what this function will do rather than what to do with that argument. All you have to do is check the type of the argument passed in and make sure it isn't any of the things listed. You can't check to see if something is an array, specifically, because an array is the same thing as an object. But, you can check if it's the other types like so:

      function arrayCounter (arr) {
        //Check to see if the passed in argument is a string, number, or undefined
        if (typeof arr == "string" || typeof arr == "number" || typeof arr == "undefined") {
          //If so, return 0, which breaks out of the function
          return 0;
        }
        else {
          //If it's not any of those things, it is of type "object" so it can be an array which is the same as an object
          return arr.length;
        }
      }

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Paul Hubbard

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How do I pass an array into a function parameter?

1 Answer

Marcus Parsons

Marcus Parsons