标签： vc

MFC通过wininet下载文件

// down.cpp : Defines the entry point for the application.
//

#include "stdafx.h"
#include <windows.h> 
#include <wininet.h>   
#include <string> 
#include <iostream>
#include <vector>
using namespace std; 
#pragma comment(lib, "wininet.lib") 




 
//下载 
#define  DOWNHELPER_AGENTNAME         "down" 
#define  LEN_OF_BUFFER_FOR_QUERYINFO  128 
#define  DOWNLOAD_BUF_SIZE            (10*1024)  //10KB 
#define  MAX_DOWNLOAD_REQUEST_TIME    10   
#define  MAX_DOWNLOAD_BYTESIZE        (1000*1024*1024) //1000MB 
 
 
BOOL _TryHttpSendRequest(LPVOID hRequest, int nMaxTryTimes); //多次发送请求函数 
 
//HTTP下载函数，通过先请求HEAD的方式然后GET，可以通过HEAD对下载的文件类型和大小做限制 
BOOL DownloadUrl(std::string strUrl, std::string strFileName) 
{ 
    BOOL bRet = FALSE; 
    if (strUrl == "" || strFileName == "") 
        return FALSE; 
 
    //定义变量 
    HINTERNET hInet = NULL; //打开internet连接handle 
    HINTERNET hConnect = NULL; //HTTP连接 
    HINTERNET hRequestHead = NULL; //HTTP Request 
    HINTERNET hRequestGet = NULL; //HTTP Request 
    HANDLE hFileWrite = NULL; //写文件的句柄 
    char* pBuf = NULL; //缓冲区 
    DWORD dwRequestTryTimes = MAX_DOWNLOAD_REQUEST_TIME; //尝试请求的次数 
    DWORD dwDownBytes = 0; //每次下载的大小 
    DWORD dwDownFileTotalBytes = 0; //下载的文件总大小 
    DWORD dwWriteBytes = 0; //写入文件的大小 
    char bufQueryInfo[LEN_OF_BUFFER_FOR_QUERYINFO] = {0}; //用来查询信息的buffer 
    DWORD dwBufQueryInfoSize = sizeof(bufQueryInfo); 
    DWORD dwStatusCode = 0; 
    DWORD dwContentLen = 0; 
    DWORD dwSizeDW = sizeof(DWORD); 
 
    //分割URL 
    CHAR pszHostName[INTERNET_MAX_HOST_NAME_LENGTH] = {0}; 
    CHAR pszUserName[INTERNET_MAX_USER_NAME_LENGTH] = {0}; 
    CHAR pszPassword[INTERNET_MAX_PASSWORD_LENGTH] = {0}; 
    CHAR pszURLPath[INTERNET_MAX_URL_LENGTH] = {0}; 
    CHAR szURL[INTERNET_MAX_URL_LENGTH] = {0}; 
    URL_COMPONENTSA urlComponents = {0}; 
    urlComponents.dwStructSize = sizeof(URL_COMPONENTSA); 
    urlComponents.lpszHostName = pszHostName; 
    urlComponents.dwHostNameLength = INTERNET_MAX_HOST_NAME_LENGTH; 
    urlComponents.lpszUserName = pszUserName; 
    urlComponents.dwUserNameLength = INTERNET_MAX_USER_NAME_LENGTH; 
    urlComponents.lpszPassword = pszPassword; 
    urlComponents.dwPasswordLength = INTERNET_MAX_PASSWORD_LENGTH; 
    urlComponents.lpszUrlPath = pszURLPath; 
    urlComponents.dwUrlPathLength = INTERNET_MAX_URL_LENGTH; 
 
    bRet = InternetCrackUrlA(strUrl.c_str(), 0, NULL, &urlComponents); 
    bRet = (bRet && urlComponents.nScheme == INTERNET_SERVICE_HTTP); 
    if (!bRet) 
    { 
        goto _END_OF_DOWNLOADURL; 
    } 
     
    //打开一个internet连接 
    hInet = InternetOpenA(DOWNHELPER_AGENTNAME, INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, NULL); 
    if (!hInet) 
    { 
        bRet = FALSE; 
        goto _END_OF_DOWNLOADURL; 
    } 
     
    //打开HTTP连接 
    hConnect = InternetConnectA(hInet, pszHostName, urlComponents.nPort, pszUserName, pszPassword, INTERNET_SERVICE_HTTP, 0, NULL); 
    if (!hConnect) 
    { 
        bRet = FALSE; 
        goto _END_OF_DOWNLOADURL; 
    } 
     
    //创建HTTP request句柄 
    if (urlComponents.dwUrlPathLength !=  0) 
        strcpy(szURL, urlComponents.lpszUrlPath); 
    else 
        strcpy(szURL, "/"); 
     
    //请求HEAD，通过HEAD获得文件大小及类型进行校验 
    hRequestHead = HttpOpenRequestA(hConnect, "HEAD", szURL, "HTTP/1.1", "", NULL, INTERNET_FLAG_RELOAD, 0); 
    bRet = _TryHttpSendRequest(hRequestHead, dwRequestTryTimes); 
    if (!bRet) 
    { 
        goto _END_OF_DOWNLOADURL; //请求HEAD失败 
    } 
    
    //查询content-length大小 
    dwContentLen = 0; 
    dwSizeDW = sizeof(DWORD); 
    bRet = HttpQueryInfo(hRequestHead, HTTP_QUERY_FLAG_NUMBER | HTTP_QUERY_CONTENT_LENGTH, &dwContentLen, &dwSizeDW, NULL); 
    if (bRet) 
    { 
        //检查是否文件过大 
        if (dwContentLen > MAX_DOWNLOAD_BYTESIZE) 
        { 
            bRet = FALSE; 
            goto _END_OF_DOWNLOADURL; 
        } 
    } 
 
    //校验完成后再请求GET，下载文件 
    hRequestGet = HttpOpenRequestA(hConnect, "GET", szURL, "HTTP/1.1", "", NULL, INTERNET_FLAG_RELOAD, 0); 
    bRet = _TryHttpSendRequest(hRequestGet, dwRequestTryTimes); 
    if (!bRet) 
    { 
        goto _END_OF_DOWNLOADURL; //请求HEAD失败 
    } 
 
    //创建文件 
    hFileWrite = CreateFileA(strFileName.c_str(), GENERIC_WRITE, FILE_SHARE_READ, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL); 
    if (INVALID_HANDLE_VALUE == hFileWrite) 
    { 
        bRet = FALSE; 
        goto _END_OF_DOWNLOADURL; 
    } 
 
    //分配缓冲 
    pBuf = new char[DOWNLOAD_BUF_SIZE]; //分配内存 
    if (!pBuf) 
    { 
        bRet = FALSE; 
        goto _END_OF_DOWNLOADURL; 
    } 
 
    //多次尝试下载文件 
    dwDownFileTotalBytes = 0; 
    while (1) 
    { 
        dwDownBytes = 0; 
        memset(pBuf, 0, DOWNLOAD_BUF_SIZE*sizeof(char)); 
        bRet = InternetReadFile(hRequestGet, pBuf, DOWNLOAD_BUF_SIZE, &dwDownBytes); 
        if (bRet) 
        { 
            if (dwDownBytes > 0) 
            { 
                dwDownFileTotalBytes += dwDownBytes; 
                bRet = WriteFile(hFileWrite, pBuf, dwDownBytes, &dwWriteBytes, NULL); //写入文件 
                if (!bRet) 
                { 
                    goto _END_OF_DOWNLOADURL; 
                } 
            } 
            else if (0 == dwDownBytes) 
            { 
                bRet = TRUE; 
                break; //下载成功完成 
            } 
        } 
    } 
     
    //清理 
_END_OF_DOWNLOADURL: 
    if (INVALID_HANDLE_VALUE != hFileWrite) 
        CloseHandle(hFileWrite); 
    if (pBuf) 
        delete [] pBuf; 
    if (hRequestGet) 
        InternetCloseHandle(hRequestGet); 
    if (hRequestHead) 
        InternetCloseHandle(hRequestHead); 
    if (hConnect) 
        InternetCloseHandle(hConnect); 
    if (hInet) 
        InternetCloseHandle(hInet); 
     
    return bRet; 
} 
 
//多次发送请求函数 
BOOL _TryHttpSendRequest(LPVOID hRequest, int nMaxTryTimes) 
{ 
    BOOL bRet = FALSE; 
    DWORD dwStatusCode = 0; 
    DWORD dwSizeDW = sizeof(DWORD); 
    while (hRequest && (nMaxTryTimes-- > 0)) //多次尝试发送请求 
    { 
        //发送请求 
        bRet = HttpSendRequestA(hRequest, NULL, 0, NULL, 0); 
        if (!bRet) 
        { 
            continue; 
        } 
        else 
        { 
            //判断HTTP返回的状态码 
            dwStatusCode = 0; 
            dwSizeDW = sizeof(DWORD); 
            bRet = HttpQueryInfo(hRequest, HTTP_QUERY_FLAG_NUMBER | HTTP_QUERY_STATUS_CODE, &dwStatusCode, &dwSizeDW, NULL); 
            if (bRet) 
            { 
                //检查状态码 
                if (HTTP_STATUS_OK == dwStatusCode) //200 OK 
                { 
                    break; 
                } 
                else 
                { 
                    bRet = FALSE; 
                    continue; 
                } 
            } 
        } 
    } 
 
    return bRet; 
} 
 

//////////////////////////////////////////////////////////////////////////

BOOL HttpGet(string url, string &result)
{
     vector<char> v; 
    const CHAR * szUrl = url.c_str(); 
    CHAR szAgent[] = ""; 
    HINTERNET hInternet1 =  
        InternetOpen(NULL,INTERNET_OPEN_TYPE_PRECONFIG,NULL,NULL,NULL); 
    if (NULL == hInternet1) 
     { 
        InternetCloseHandle(hInternet1); 
        return FALSE; 
     } 
    HINTERNET hInternet2 =  
        InternetOpenUrl(hInternet1,szUrl,NULL,NULL,INTERNET_FLAG_NO_CACHE_WRITE,NULL); 
    if (NULL == hInternet2) 
     { 
        InternetCloseHandle(hInternet2); 
        InternetCloseHandle(hInternet1); 
        return FALSE; 
     } 
    DWORD dwMaxDataLength = 500; 
    PBYTE pBuf = (PBYTE)malloc(dwMaxDataLength*sizeof(TCHAR)); 
    if (NULL == pBuf) 
     { 
        InternetCloseHandle(hInternet2); 
        InternetCloseHandle(hInternet1); 
        return FALSE; 
     } 
    DWORD dwReadDataLength = NULL; 
    BOOL bRet = TRUE; 
    do  
    { 
        ZeroMemory(pBuf,dwMaxDataLength*sizeof(TCHAR)); 
        bRet = InternetReadFile(hInternet2,pBuf,dwMaxDataLength,&dwReadDataLength); 
        for (DWORD dw = 0;dw < dwReadDataLength;dw++) 
          { 
            v.push_back(pBuf[dw]); 
          } 
     } while (NULL != dwReadDataLength); 

    vector<char>::iterator i; 
    for(i=v.begin(); i!=v.end(); i++) 
        result += *i;

     return TRUE;
}

//////////////////////////////////////////////////////////////////////////
 
/*
int main(int argc, char* argv[]) 
{ 
    cout << "正在下载..."; 
    BOOL bR = DownloadUrl("http://42.duote.com.cn/office2007.zip", "test.zip"); 
    if (bR) 
        cout << "完成" << endl; 
    else 
        cout << "失败" << endl; 
    return 0; 
}
*/


string trim(const string& str)
{
     string::size_type pos = str.find_first_not_of(' ');
     if (pos == string::npos)
     {
          return str;
     }
     string::size_type pos2 = str.find_last_not_of(' ');
     if (pos2 != string::npos)
     {
          return str.substr(pos, pos2 - pos + 1);
     }
     return str.substr(pos);
}

int split(const string& str, vector<string>& ret_, string sep = ",")
{
     if (str.empty())
     {
          return 0;
     }
    
     string tmp;
     string::size_type pos_begin = str.find_first_not_of(sep);
     string::size_type comma_pos = 0;
    
     while (pos_begin != string::npos)
     {
          comma_pos = str.find(sep, pos_begin);
          if (comma_pos != string::npos)
          {
               tmp = str.substr(pos_begin, comma_pos - pos_begin);
               pos_begin = comma_pos + sep.length();
          }
          else
          {
               tmp = str.substr(pos_begin);
               pos_begin = comma_pos;
          }
         
          if (!tmp.empty())
          {
               ret_.push_back(tmp);
               tmp = "";
          }
     }
     return 0;
}

string replace(const string& str, const string& src, const string& dest)
{
     string ret;
    
     string::size_type pos_begin = 0;
     string::size_type pos       = str.find(src);
     while (pos != string::npos)
     {
          cout <<"replacexxx:" << pos_begin <<" " << pos <<"\n";
          ret.append(str.data() + pos_begin, pos - pos_begin);
          ret += dest;
          pos_begin = pos + 1;
          pos       = str.find(src, pos_begin);
     }
     if (pos_begin < str.length())
     {
          ret.append(str.begin() + pos_begin, str.end());
     }
     return ret;
}

void Debug(string str)
{    
     MessageBox(NULL, str.c_str(), "DEBUG", MB_OK);
}


int APIENTRY WinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR     lpCmdLine,
                     int       nCmdShow)
{
     string html;
     if (!HttpGet("http://42.96.190.81:81/list.txt", html))
     {
          MessageBox(NULL, "列表获取失败！", "ERROR", MB_OK);
          return 0;
     }
    

     vector<string> urls;
     split(html, urls, "\r\n");
     for(int i=0; i<urls.size(); i++)
     {
          size_t pos = urls[i].rfind('/', urls[i].size());
          string fileName = urls[i].substr(pos+1, urls[i].size()-pos-1);

          if (DownloadUrl(urls[i], fileName))
          {
               Debug(fileName + "下载成功");

          }

     }
     Debug("完成");



     return 0;
}

AfxBeginThread是MFC封装的函数，返回的是CWinThread*，不能用于CloseHandle。AfxBeginThread在线程执行完后会句柄资源自动释放。

如果是::CreateThread创建的线程则要手工调用CloseHandle释放线程句柄。