Exception in Directory.CreateDirectory when folder name ends with whitespace

[cpaul06]

I'm getting inconsistent results when calling Directory.CreateDirectory in a .NETCoreApp 1.0 and 2.0 compared to .NETFramework 4.6.2.

If the folder ends with a whitespace but doesn't contain any whitespaces in the name:
Directory.CreateDirectory("c:\work\CreateDirectory\folder \inner") Directory.CreateDirectory("c:\work\CreateDirectory\ folder \inner")
will throw an exception:
at System.IO.Win32FileSystem.CreateDirectory(String fullPath)
at System.IO.Directory.CreateDirectory(String path)
at TrailingNETCore.Program.ValidateCreate(String path, String netFrameworkResult) in C:\source\TrailingWhiteSpace\TrailingWhiteSpace\TrailingNETCore\Program.cs:line 55

If the folder ends with a whitespace but contains whitespaces in the name:
Directory.CreateDirectory("c:\work\CreateDirectory\fold er \inner") Directory.CreateDirectory("c:\work\CreateDirectory\ fol der \inner")
will get different results than .NETFramework.

I attached an example program with various use cases and a comparison against .NETFramework
CreateDirectory.zip

[danmoseley]

@nchikanov maybe this is something you'd be interested to investigate.

[JeremyKuhne]

You cannot create a file or directory name that has trailing spaces or periods without using \\?\ at the beginning of the path. If you see that not working please reactivate. We explicitly do not want to support creating such paths without the syntax (e.g. adding it implicitly) as most apps can't handle it.