I'm trying to make a level editor that uses XML, so I started with this script on the Unify Wiki. But it won't compile as-is--it says `'Delete' is not a member of 'System.IO.FileInfo'.` What's up? That's the only error it throws and if I take that line out it compiles, but it's a pretty important feature.
There are some .NET features that you can't use from a Web Player build, and System.IO.FileInfo.Delete seems to be one of them. If you switch your build settings (File > Build Settings ... > Switch Platform) to Mac or PC Standalone then it should work.
Have a look at the C# preprocessor options to allow your codebase to compile in multiple contexts.