check vcxproj files for non-existent header files causing MSBuild to rebuild

CheckProjectFileHeadersExist.cs

using System;
using System.IO;
using System.Xml.Linq;

static class Program
{
	static void check(string fileName)
	{
		XDocument project = XDocument.Load(fileName);
		XNamespace msbuild = XNamespace.Get("http://schemas.microsoft.com/developer/msbuild/2003");

		int present = 0, missing = 0;
		string folder = Path.GetDirectoryName(fileName);
		foreach (XElement elem in project.Root.Elements(msbuild + "ItemGroup").Elements(msbuild + "ClInclude"))
		{
			string name = (string)elem.Attribute("Include");
			string itemPath = Path.Combine(folder, name);
			if (!File.Exists(itemPath))
			{
				Console.WriteLine(name);
				missing++;
			}
			else
			{
				present++;
			}
		}

		Console.WriteLine("{0} files present, {1} missing.", present, missing);
	}

	static void Main(string[] args)
	{
		check(args[0]);
		check(Path.ChangeExtension(args[0], ".vcxproj.filters"));
	}
}