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JavaScript JavaScript Foundations Functions Return Values

Robert Farese
Robert Farese
7,944 Points
Posted by Robert Farese
Robert Farese
7,944 Points

I don't think I wrote this code in the most efficient way...

Here is how I answered this question...which came out correct but I can't imagine I wrote this in the most effective way. How can I consolidate all these if statements?

function arrayCounter (myArray) { if (typeof myArray === ‘string’){ return 0; } if (typeof myArray === ‘number’){ return 0; } if (typeof myArray === ‘undefined’){ return 0; } return myArray.length; }

2 Answers

Andrew Shook
Andrew Shook
31,709 Points
Andrew Shook
Andrew Shook
31,709 Points

They didn't teach it during the course, but the most effective way to do this is to use isArray.

function arrayCounter( myArray){
    if( Array.isArray( myArray ) ){
        return myArray.length;
    }
    return 0;
}
Robert Farese
Robert Farese
7,944 Points
Robert Farese
Robert Farese
7,944 Points

Hey Andrew! That's exactly what I was looking for. Thanks for your help!

Jeff Busch
Jeff Busch
19,287 Points
Jeff Busch
Jeff Busch
19,287 Points

Hi Robert,

You can try this:

function arrayCounter (myArray) {
    if(typeof myArray === 'string' || typeof myArray === 'number' || typeof myArray === 'undefined') {
        return 0;
    } else {
    return myArray.length;
    }
}
Robert Farese
Robert Farese
7,944 Points
Robert Farese
Robert Farese
7,944 Points

Thanks Jeff! I had thought of using that operator...