Skipping Over Null Values In InnerHTML

I am having difficulty in skipping over null values when using .innerHTML i have something like this:

var inputLastIndexValue = document.getElementById("FileCount").innerHTML;
var inputArray = [];

for(var indexCounter = 0; indexCounter <= inputLastIndexValue; indexCounter++){
    var elementID = indexCounter + ".File";
        console.log("ElementID: " + elementID);

        if(document.getElementById(elementID).innerHTML)
        {
            inputArray[indexCounter] =  document.getElementById(elementID).innerHTML;;
            console.log(inputArray[indexCounter] + ":" + indexCounter);

        }

What I am trying to accomplish is getting the names of files that I upload to populate an array in which I can search from. I know for a fact that this script halts and throws a null error when trying to find something that does not exist.

As the error is trying to tell you, you can't access document.getElementById(elementID).innerHTML if document.getElementById(elementID) is null.

You need to check whether the element itself exists.