Instant control over file and folder operations in Windows and .NET applications

Installing .NET component into Visual Studio

.NET component is contained in CBFlt4Net.dll, located subfolders of in <CallbackFilter>\dotNET\ folder. CBFlt4Net.dll requires MSVC Runtime DLLs. Please refer to Deployment instructions for details on installing those Runtime DLLs on your system for development and on target systems during deployment.

To install components to Visual Studio Toolbox

  1. Use Main Menu -> Tools -> Choose Toolbox items to open Toolbox Customization dialog
  2. In the dialog that appears activate .NET Framework Components tab
  3. Find CallbackFilter component in the list and check it.
  4. If you don't find the component in the list, use Browse button to find and add the assembly, which contains the component, to the list.
    Assemblies (32-bit and 64-bit) for .NET 4.6 are located in <CallbackFilter>\dotNET\NET_46 folder.
    Assemblies (32-bit and 64-bit) for .NET 4.5.1 are located in <CallbackFilter>\dotNET\NET_451 folder.
    Assemblies (32-bit and 64-bit) for .NET 4.5 are located in <CallbackFilter>\dotNET\NET_45 folder.
    Assemblies (32-bit and 64-bit) for .NET 4.0 are located in <CallbackFilter>\dotNET\NET_40 folder.
    Assemblies (32-bit and 64-bit) for .NET 2.0 are located in <CallbackFilter>\dotNET\NET_20 folder.

Using the components

To use CallbackFilter in your project, you need to include CBFlt4Net.dll to the list of project references. Then, in source file, add the following line:

  • C#:
    using CbFlt;
  • VB.NET:
    imports CbFlt;
  • C++:
    #using <CBFlt4Net.dll>

Referencing plastform-specific assemblies from AnyCPU project

To use CallbackFilter in your AnyCPU project, you need to tell the loader, how to find and load the assembly, which matches your architecture. The sample code in C#-based pseudocode is provided below. The code assumes that you have copies of the assembly, stored in "x86" and "x64" subdirectories of your project's directory. Be sure to turn off "Copy local" option for the assembly reference, so that the compiler doesn't make a (wrong) copy of the assembly to the directory with your project assemblies.

AppDomain.CurrentDomain.AssemblyResolve += PlatformDepResolve;
private static Assembly PlatformDepResolve(object sender, ResolveEventArgs args)
	string AsmName = "CBFlt4Net";
	if (args.Name.StartsWith(AsmName))
		string architecture;
		if (Environment.Is64BitOperatingSystem)
			architecture = "x64";
			architecture = "x86";

		string fileName = Path.Combine(Environment.CurrentDirectory,
			architecture, AsmName + ".dll");
		Assembly assembly = Assembly.LoadFile(fileName);
		if (args.Name == assembly.FullName)
			return assembly;
		return null;
Thanks to Tyrone Erasmus for the custom resolver implementation.

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