非同期ドロップ処理フリースレッドマーシャラー + CFSTR_FILEDESCRIPTOR (Windows Forms)

FileDescriptorTest-Forms-Async-FTM.cpp

#define UNICODE
#define _UNICODE

#define _CRT_SECURE_CPP_OVERLOAD_STANDARD_NAMES 1
#define _CRT_SECURE_CPP_OVERLOAD_SECURE_NAMES 1

#define WINVER 0x0600
#define _WIN32_WINNT 0x0600

#include <string.h>

#include <Windows.h>
#include <ShlObj.h>

#using <System.dll>
#using <System.Windows.Forms.dll>

using namespace System;
using namespace System::Diagnostics;
using namespace System::IO;
using namespace System::Runtime::InteropServices;
using namespace System::Threading;
using namespace System::Windows::Forms;

namespace ComTypes = System::Runtime::InteropServices::ComTypes;

namespace NativeTypes
{
	[ComVisible(true)]
	[InterfaceTypeAttribute(ComInterfaceType::InterfaceIsIUnknown)]
	[GuidAttribute("3D8B0590-F691-11d2-8EA9-006097DF5BD4")]
	public interface class IDataObjectAsyncCapability
	{
	public:
		void SetAsyncMode([MarshalAs(UnmanagedType::Bool)] bool fDoOpAsync);
		[returnvalue:MarshalAs(UnmanagedType::Bool)]
		bool GetAsyncMode();
		void StartOperation(ComTypes::IBindCtx^ pbcReserved);
		[returnvalue:MarshalAs(UnmanagedType::Bool)]
		bool InOperation();
		void EndOperation(HRESULT hResult, ComTypes::IBindCtx^ pbcReserved, DWORD dwEffects);
	};
}

ref class AsyncDataObject : public DataObject, public NativeTypes::IDataObjectAsyncCapability
{
public:
	virtual void SetAsyncMode([MarshalAs(UnmanagedType::Bool)] bool fDoOpAsync)
	{
		if (fDoOpAsync == false)
		{
			throw gcnew ArgumentException();
		}
	}
	[returnvalue:MarshalAs(UnmanagedType::Bool)]
	virtual bool GetAsyncMode()
	{
		return true;
	}
	virtual void StartOperation(ComTypes::IBindCtx^ /*pbcReserved*/)
	{
		Debug::WriteLine("StartOperation: " + Thread::CurrentThread->ManagedThreadId);
		Interlocked::Increment(m_inOperationCount);
	}
	[returnvalue:MarshalAs(UnmanagedType::Bool)]
	virtual bool InOperation()
	{
		return m_inOperationCount > 0;
	}
	virtual void EndOperation(HRESULT /*hResult*/, ComTypes::IBindCtx^ /*pbcReserved*/, DWORD /*dwEffects*/)
	{
		Debug::WriteLine("EndOperation: " + Thread::CurrentThread->ManagedThreadId);
		Interlocked::Decrement(m_inOperationCount);
	}

private:
	int m_inOperationCount = 0;
};

DataObject^ GetFileDescriptorAndContent()
{
	auto dataObj = gcnew AsyncDataObject;
	auto buffer = gcnew array<BYTE>(sizeof FILEGROUPDESCRIPTOR);
	pin_ptr<BYTE> p = &buffer[0];
	auto fileGroupDescriptor = reinterpret_cast<FILEGROUPDESCRIPTOR*>(p);
	fileGroupDescriptor->cItems = 1;
	fileGroupDescriptor->fgd[0].dwFlags = static_cast<DWORD>(FD_PROGRESSUI | FD_UNICODE);
	wcscpy_s(fileGroupDescriptor->fgd[0].cFileName, L"test.txt");
	dataObj->SetData(CFSTR_FILEDESCRIPTOR, gcnew MemoryStream(buffer));

	auto data = gcnew array<BYTE> { 'a', 'b', 'c' };
	auto content = gcnew MemoryStream;
	content->Write(data, 0, data->Length);
	dataObj->SetData(CFSTR_FILECONTENTS, content);

	return dataObj;
}

void OnMouseDown(Object^ sender, MouseEventArgs^ e)
{
	if ((e->Button & MouseButtons::Left) != MouseButtons())
	{
		Debug::WriteLine("Before DoDragDrop: " + Thread::CurrentThread->ManagedThreadId);
		safe_cast<Control^>(sender)->DoDragDrop(GetFileDescriptorAndContent(), DragDropEffects::Copy);
		Debug::WriteLine("After DoDragDrop: " + Thread::CurrentThread->ManagedThreadId);
	}
}

[STAThread]
int main(array<System::String ^> ^args)
{
	auto f = gcnew Form;
	f->MouseDown += gcnew MouseEventHandler(OnMouseDown);
	Application::Run(f);
	return 0;
}