Check ASPX files to make sure that Resource Key referenced exsists in RESX

I have a rather large website that had its strings externalized. I wanted to know if there was a way to check to make sure that a resource object in the ASPX exists in the resource file that is being referenced? There are a few pages that get parser errors, but I want to be able to batch check all the files.

If there is a tool or some way to check all the files and you know how I would greatly appreciate if you would be able to assist me in this.