httpthread.cpp

INTERNET网络高级编程的包括邮件加密、MAPI、ISAPI、ACTIVEX、FTP等等。

// HttpThread.cpp: implementation of the CHttpThread class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "HttpEx.h"
#include "HttpThread.h"

#include <wininet.h>


#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CHttpThread::CHttpThread(): m_hPostMsgWnd(NULL), 
           lpszBuf(NULL)
{
   
}

CHttpThread::~CHttpThread()
{
    if(lpszBuf)
         delete lpszBuf;

}

void CHttpThread::InitHttp(HWND hPostMsgWnd)
{
		m_hPostMsgWnd = hPostMsgWnd ;
}

    
char*CHttpThread:: GetBuffer()
{
		return lpszBuf;
}
void CHttpThread::GetHttpFile(CString& strAddress)
{
    CString strTemp=strAddress.Mid(7);
	//检查主机的路径
	int nSlash=strTemp.Find("/");
	if (nSlash!=-1)  //如等于-1，就是没找到
	{
		m_strServer=strTemp.Left(nSlash);//取‘/’左边的服务器地址
        m_strPath=strTemp.Mid(nSlash);
	}
	else
	{
		m_strServer=strTemp;
	}
	AfxBeginThread(GetHttpFileWorkerThread, this);
}

UINT CHttpThread::GetHttpFileWorkerThread(LPVOID pvThread)
{
   	CHttpThread *pthread=(CHttpThread *)pvThread;
		
	if(pthread==NULL
		     ||pthread->m_strServer.IsEmpty()
		         ||pthread->m_hPostMsgWnd==NULL)
		{
				return 0;
		 }
	pthread->_GetHttpFile();
	return 1;
}

UINT CHttpThread::_GetHttpFile()
{
	 //第一步:初始化internet DLL,这是第一个被调用的函数
	HINTERNET hSession=::InternetOpen("Raw HTML Reader",PRE_CONFIG_INTERNET_ACCESS,
		                              "",INTERNET_INVALID_PORT_NUMBER,0);

	//判断会话句柄是否有效
	if(hSession==NULL)
	{
		AfxMessageBox("Internet session initalization failed!");
		return 0;
	}
	//第二步：初始化HTTP session
	HINTERNET	hConnect=::InternetConnect(hSession,//当前internet会话句柄
		                                   m_strServer,//server name
										   INTERNET_INVALID_PORT_NUMBER,
										   "",//user name
										   "",//password
										   INTERNET_SERVICE_HTTP,//Type of service to access
										   0,
										   0);
	//判断连接句柄是否有效
	if(hConnect==NULL)
	{
		AfxMessageBox("Internet connect initalization failed!");
		//关闭会话句柄
		VERIFY(::InternetCloseHandle(hSession));
		return 0;
	}
	
    //第三步：打开一个HTTP请求句柄
	HINTERNET hHttpFile=::HttpOpenRequest(hConnect,
										  "GET",
										  m_strPath,
										  HTTP_VERSION,
										  NULL,
										  0,
										  INTERNET_FLAG_DONT_CACHE,
										  0);
	//判断连接句柄是否有效
	//判断会话句柄是否有效
	if(hHttpFile==NULL)
	{
		AfxMessageBox("Http request failed!");
		VERIFY(::InternetCloseHandle(hConnect));
		VERIFY(::InternetCloseHandle(hSession));
		return 0;
	}
	
	//显示等待光标
	CWaitCursor wait;

	//第四步：发出请求
	BOOL bSendRequest=::HttpSendRequest(hHttpFile,
									   NULL,
									   0,
									   0,
									   0);
	if(bSendRequest)
	{
		//得到文件的大小
		char achQueryBuf[32];
		DWORD dwFileSize;
		DWORD dwQueryBufLen=sizeof(achQueryBuf);
		BOOL bQuery=::HttpQueryInfo(hHttpFile,
			                        HTTP_QUERY_CONTENT_LENGTH,
									achQueryBuf,
									&dwQueryBufLen,
									NULL);

		if(bQuery)
		{
			//查找成功，指出需要存放文件的内存大小???????
            dwFileSize=(DWORD)atol(achQueryBuf);
		}
		else
		{
			//失败，猜出一个最大文件数
			dwFileSize=5*1024;
		}

		//分配一个缓冲区给文件数据
		lpszBuf=NULL;
		lpszBuf=new char[dwFileSize+1];

	    //读文件
		DWORD dwBytesRead=0;
		BOOL bRead=::InternetReadFile(hHttpFile,
			                          lpszBuf,
									  dwFileSize+1,
									  &dwBytesRead);
	
      if(bRead)
	  {
		  lpszBuf[dwBytesRead]=0;
	  }
      

		// 关闭INTERNET句柄
		VERIFY(::InternetCloseHandle(hHttpFile));
		VERIFY(::InternetCloseHandle(hConnect));
		VERIFY(::InternetCloseHandle(hSession));    
	
		PostMessage(m_hPostMsgWnd,WM_READFILECOMPLETED,NULL,NULL);	

	}

	return TRUE;  // return TRUE unless you set the focus to a control
	              // EXCEPTION: OCX Property Pages should return FALSE
}