NC-DokanFsBase 0.1.1

NC-DokanFsBase

This library will help you create new Dokan User Mode File System quicker and easier.

Why you need this library?

When implementing new File System for Dokan, you would be implementing IDokanOperations interface and writing roughly 24 functions.

Although the functions in IDokanOperations seems trivial, you would face a lot of trouble creating a working file system because you do not know how to correctly respond to each calls made to your IDokanOperations.

Fortunately, Dokan-net has provided Mirror.cs which seems to have encapsulated the knowledge of creating a working file system in Dokan. The Mirror sample use File/Directory/Path classes in System.IO namespace to handle the requests.

I have extracted those calls into an interface called IDokanDisk which is available to you in this Library. So you can implement a working File system without having an in-depth understanding of why CreateFile function gets called when Windows Explorer trying to list files in a folder!

Implementation Steps

1. Create a new class which implements IDokanDisk. There are 22 functions to implement, just be patient and follow the guide in XML Comments. Trust me, it's a lot more trivial than having to implement CreateFile function in IDokanOperations which does almost everything.

using NC.DokanFS;

namespace NC.CrossDrive.App
{
    public class CrossDriveDokanDisk : IDokanDisk
    {
        // implement the operations here
    }
}

2. Create a new class which implments IDokanFileContext. Your IDokanDisk's CreateFileContext function should return a new instance of this class.

This class is where you will perform read/write operations to your backend storage. If you do not want to support an operation, just throw IOException

Flush method will be called when the application request the write buffer to be flushed - so do that!

The Dispose method of this class will gets called when an application using the file close the file handle. So in Dispose, make sure to clean up everything related to the file.

using NC.DokanFS;
namespace NC.CrossDrive.App
{
    public class CrossDriveFileContext : IDokanFileContext
    {
        // implement Read, Close, Flush Dispose
    }
}

3. Create new instance of DokanFrontend and pass an instance of your IDokanDisk to it. DokanFrontend class is the modified Mirror.cs sample which calls to IDokanDisk instead of vairous System.IO.* classes.

using NC.DokanFS;
namespace NC.CrossDrive.App
{
    class Program
    {
        static void Main(string[] args)
        {
            var crossdrive = new CrossDriveDokanDisk();
            var dokan = new DokanFrontend(crossdrive, "CrossDrive");
            dokan.Mount(@"H:\");

            Console.WriteLine("Press ENTER to Exit.");
            Console.Read();

            dokan.Unmount();
        }
    }
}

Run and enjoy your new file system!

Base Classes in NC.DokanFS.Specialized

There are few helpful classes in this namespace to help you get started even faster.

• ReadOnlyDiskBase : inherit this class to create a read-only file system
• ReadOnlyFileContextBase : inherit this class for read-only file context
• BlockBasedReadOnlyFileContextBase : inherit this class for read-only file context which fetch data from backend storage in blocks
• BlockBasedFileContextBase : inherit this class for file context which fetch/write data from backend storage in blocks

License

MIT License.