Javascript for next loop but in reverse

I have a loop.  But it's REMOVING invalid file extensions... see below.

var items = response.split("\n");
var myItemsOrgLength = items.length;
var myListOfExt = [];      
//alert(items.length);
var y;
//remove any items where the file extension is not in the validTypes list
for (x= items.length - 1; x >= 0; x--)
{
      fields = items[x].split("\t");
      // split filename into fields on the ".", then pop the last field from the stack: the file extension
      var ext = fields[1].split(".").pop();
            
            if (!contains(validTypes, ext))
      {
          myListOfExt[x] = ext;
          items.splice(x,1);
      }
    }
Just so you know, validTypes is a comma delimited strting from an XML file of acceptable file types.: example:  pdf,doc,docx,jpg,tif.... and so on.

The problem is, that the array doesn't start at ZERO but starts at 1, thus throwing off my array LENGTH.

Any thoughts?

here's the contains() function:

            function contains(array, value)
            {
              value = value.toUpperCase();
             
              for (var x= 0; x< array.length; x++)
                    if (array[x].toUpperCase() == value)
                          return true;
                    return false;
            }
pborreggAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Ivo StoykovCommented:
just add a check whether item exists...

HTH

Ivo Stoykov

for (x= items.length - 1; x >= 0; x--)
{
// check whether it is valid item
      if(!items[0]) {  continue;  }
      fields = items[x].split("\t");

Open in new window

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
pborreggAuthor Commented:
Cool
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
JavaScript

From novice to tech pro — start learning today.