How to do Synchronous and Asynchronous web downloads

/*
Author		: Nishant S
EMail		: nishforever@vsnl.com
Date		: June 28th 2002
Notes		: Demo app for Code Project article
*/
#include "stdafx.h"

#using <mscorlib.dll>
#using <system.dll>
#include <tchar.h>

using namespace System;
using namespace System::IO;
using namespace System::Net;
using namespace System::Threading;
using namespace System::Text;

__gc class WebStuffDemo
{
public:
	void DownloadFile(String* url, String* fpath)
	{
		WebRequest* wrq = WebRequest::Create(url);
		HttpWebResponse* hwr = static_cast<HttpWebResponse*>(wrq->GetResponse());
		Stream* strm = hwr->GetResponseStream();
		FileStream* fs = new FileStream(fpath,FileMode::Create,FileAccess::Write);
		BinaryWriter* br = new BinaryWriter(fs);
		int b;
		while((b=strm->ReadByte()) != -1)
		{
			br->Write(Convert::ToByte(b));
		}
		br->Close();
		strm->Close();
	}
	void DownloadFileAsync(String* url, String* fpath)
	{
		WebRequest* wrq = WebRequest::Create(url);
		finished = new ManualResetEvent(false);
		m_writeEvent = new AutoResetEvent(true);
		buffer = new unsigned char __gc[512];
		OutFile = new FileStream(fpath,
			FileMode::Create,FileAccess::Write);
		wrq->BeginGetResponse(
			new AsyncCallback(this,WebStuffDemo::ResponseCallback),
			wrq);
		finished->WaitOne();
		OutFile->Close();		
	}
private:
	ManualResetEvent* finished;
	AutoResetEvent* m_writeEvent;
	unsigned char buffer __gc[];
	FileStream* OutFile;
	void ResponseCallback(IAsyncResult* ar)
	{
		WebRequest* wrq = static_cast<WebRequest*>(ar->AsyncState);
		WebResponse* wrp = wrq->EndGetResponse(ar);		
		Stream* strm = wrp->GetResponseStream();
		strm->BeginRead(buffer,0,512,
			new AsyncCallback(this,WebStuffDemo::ReadCallBack),strm);
	}
	void ReadCallBack(IAsyncResult* ar)
	{
		Stream* strm = static_cast<Stream*>(ar->AsyncState);
		int count = strm->EndRead(ar);
		if(count > 0)
		{
			__wchar_t Temp __gc[] = new __wchar_t __gc[512];
			Decoder* d = Encoding::UTF8->GetDecoder();
			d->GetChars(buffer,0,buffer->Length,Temp,0);
			String* s = new String(Temp,0,count);
			Console::WriteLine(s->Length);
			unsigned char wbuff __gc[] = new unsigned char __gc[512];			
			
			buffer->CopyTo(wbuff,0);
			
			OutFile->BeginWrite(wbuff,0,count,
				new AsyncCallback(this,WebStuffDemo::WriteCallBack),OutFile);
			
			strm->BeginRead(buffer,0,512,
				new AsyncCallback(this,WebStuffDemo::ReadCallBack),strm);
		}
		else
		{
			strm->Close();
			finished->Set();
		}
	}
	void WriteCallBack(IAsyncResult* ar)
	{
		m_writeEvent->WaitOne();
		FileStream* out = static_cast<FileStream*>(ar->AsyncState);
		out->EndWrite(ar);
		m_writeEvent->Set();
	}

};

int _tmain(void)
{
	WebStuffDemo* wsd = new WebStuffDemo(); 
	wsd->DownloadFile("http://www.codeproject.com/styles/global.css",
		"d:\\global1.css");
	wsd->DownloadFileAsync("http://www.codeproject.com/styles/global.css",
		"d:\\global2.css");
    return 0;
}