How do I determine whether the filesystem is case-sensitive in .net?

Question

Does .net have a way to determine whether the local filesystem is case-sensitive?

Answer 1

You can create a file in the temp folder (using lowercase filename), then check if the file exists (using uppercase filename), e.g:

string file = Path.GetTempPath() + Guid.NewGuid().ToString().ToLower();
File.CreateText(file).Close();
bool isCaseInsensitive = File.Exists(file.ToUpper());
File.Delete(file);

Answer 2

Here is the approach that does not use temporary files:

using System;
using System.Runtime.InteropServices;

static bool IsCaseSensitive()
{
    if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ||
        RuntimeInformation.IsOSPlatform(OSPlatform.OSX))  // HFS+ (the Mac file-system) is usually configured to be case insensitive.
    {
        return false;
    }
    else if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
    {
        return true;
    }
    else if (Environment.OSVersion.Platform == PlatformID.Unix)
    {
        return true;
    }
    else
    {
       // A default.
       return false;
    }
}

Instead, it contains an ingrained knowledge about operating environments.

Readily available as NuGet package, works on everything .NET 4.0+ and updated on a regular basis: https://github.com/gapotchenko/Gapotchenko.FX/tree/master/Source/Gapotchenko.FX.IO#iscasesensitive