How to check if array element exists or not in javascript?

Question

I am working with Titanium, my code looks like this:

var currentData = new Array();

if(currentData[index]!==\"\"||currentData[index]!==null||currentData[ind         


        

Answer 1

(typeof files[1] === undefined)?
            this.props.upload({file: files}):
            this.props.postMultipleUpload({file: files widgetIndex: 0, id})

Check if the second item in the array is undefined using the typeof and checking for undefined