C# .NET - How to Check if Sub-directory Exists in ASP.NET Medium Trust

Asked By Patrick Skelton on 18-Mar-13 03:35 PM
Hi,

To emulate my hosting provider, I have set up my local IIS in Windows 7 to run Medium Trust.  Microsoft say that, in Medium Trust, you have restricted FileIOPermission.  This seems to be correct because I have the following entry in my \Windows\Microsoft.NET\Framework\v4.0.30319\Config\web_mediumtrust.config file:


<IPermission

  class="FileIOPermission"

  version="1"

  Read="$AppDir$"

  Write="$AppDir$"

  Append="$AppDir$"

  PathDiscovery="$AppDir$"


I am trying to discover if a sub-directory exists in my application's root folder. I would have thought this would be okay, since I have PathDiscovery permission, but when I try the following:


DirectoryInfo logFileDirectoryInfo = new DirectoryInfo( @"\logs" );


I get a security exception, which simply says I do not have FileIOPermission.


Can anyone tell me what I am doing wrong?  Is there another way to check if a sub-directory exists without causing this exception?


Any help or advice would be very much appreciated.


Kind wishes, Patrick