how to create an image of a disk?

I'm developing in .net, but can use c++. I'm looking for a way to create a disk image. Ideally there could be an API somewhere that looks like this开发者_C百科:

createVMDK(string driveLetter, out string pathToVMDKOutputfile);
createVHD(string driveLetter, out string pathToVHDOutputfile);

Does anyone know of any API from Microsoft, VMWare or other that allows for the creation of full disk images like this?

If there's no API, you can invoke Disk2VHD in a Process:

disk2vhd <[drive: [drive:]…]|[*]> <vhdfile>