Chessar.LongPaths 1.1.8

dotnet add package Chessar.LongPaths --version 1.1.8                
NuGet\Install-Package Chessar.LongPaths -Version 1.1.8                
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.
<PackageReference Include="Chessar.LongPaths" Version="1.1.8" />                
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add Chessar.LongPaths --version 1.1.8                
#r "nuget: Chessar.LongPaths, 1.1.8"                
#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package.
// Install Chessar.LongPaths as a Cake Addin
#addin nuget:?package=Chessar.LongPaths&version=1.1.8

// Install Chessar.LongPaths as a Cake Tool
#tool nuget:?package=Chessar.LongPaths&version=1.1.8                

Version Downloads License Platforms Language Coverage

Chessar.LongPaths is a .NET library that allows you to enable long path support for the main System.IO classes:

FileStream, File, FileInfo, Directory, DirectoryInfo, ... (and others).

The library is based on replacing the internal NormalizePath and GetFullPathInternal functions from the static Path class. The replacement is done using JMP hooks (thanks to @wledfor2), in which the long path prefix \\?\ or \\?\UNC\ is added. Adding a prefix is done by calling the internal function Path.AddLongPathPrefix. Note also that the addition of such prefixes depends on the UseLegacyPathHandling and BlockLongPaths settings, which must necessarily be false (in the AppContextSwitchOverrides element).

In this case, your code does not need to directly add such prefixes to the paths.

Supported Platforms:

How to use

  1. Add the Chessar.LongPaths NuGet package to the project.
  2. In the file app.config (or web.config), in the section runtime, add:
    <AppContextSwitchOverrides value="Switch.System.IO.UseLegacyPathHandling=false;Switch.System.IO.BlockLongPaths=false" />
  1. In the code (when you start the application or at the beginning of Main) add code:
using static Chessar.Hooks;

  1. Usage
var fileInfo = new FileInfo(path);
var fullName = fileInfo.FullName; // with long path prefix
  1. At the end of the application:

See also Examples.


Next methods does not work for long paths, even if a prefix is added:

  1. For the following methods:
using static Chessar.Hooks;

    var di = new DirectoryInfo(...);


  1. Add long path support in methods from Notes.
  2. Make hooks more thread safe.



Product Compatible and additional computed target framework versions.
.NET Framework net462 is compatible.  net463 was computed.  net47 was computed.  net471 was computed.  net472 was computed.  net48 was computed.  net481 was computed. 
Compatible target framework(s)
Included target framework(s) (in package)
Learn more about Target Frameworks and .NET Standard.
  • .NETFramework 4.6.2

    • No dependencies.

NuGet packages

This package is not used by any NuGet packages.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last updated
1.1.8 1,580 10/25/2018
1.1.7 767 10/2/2018
1.1.7-rc003 578 10/2/2018
1.1.6 748 9/24/2018
1.1.5 722 9/23/2018
1.1.4 758 9/21/2018
1.1.3 745 9/20/2018
1.1.2 753 9/16/2018
1.1.1 768 9/12/2018
1.1.0 772 9/10/2018
1.0.9 820 9/4/2018
1.0.8 785 8/26/2018
1.0.7 829 7/30/2018
1.0.6 782 7/25/2018
1.0.5 805 7/19/2018
1.0.4 883 7/18/2018
1.0.3 899 7/18/2018
1.0.2 894 7/18/2018
1.0.1 926 7/12/2018
1.0.0 893 7/12/2018
1.0.0-rc005 664 7/5/2018
1.0.0-rc004 737 6/20/2018
1.0.0-rc003 729 6/18/2018

Fixed enumerating of FS items for a drive letter