WinInet 小例子

#include <windows.h>
#include <wininet.h>  

#include <string>
#include <iostream>
#include <fstream>

using namespace std;  

#pragma comment(lib, "wininet.lib")  

//下载
#define  DOWNHELPER_AGENTNAME         "MyAppByMulinB"
#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;

}  

//打开文件函数

ifstream& openFile(ifstream& in, const string& fileName)
{
  in.close();
  in.clear();
  in.open(fileName.c_str()); 

  return in;
} 

int main(int argc, char* argv[])
{
    BOOL bR,bRet;
    cout << "正在下载..."<<endl;
    /*
    string  str;
    ifstream fread;
    if (openFile(fread, "港股.txt"))
    {
        while (fread >> str )
        {
            bR = DownloadUrl("http://real-chart.finance.yahoo.com/table.csv?s="+str+"&d=06&e=01&f=2015&g=d&a=00&b=01&c=2013&ignore=.csv", str+".txt");//2013年1月1号——2015年6月29号
            if (!bR)
                //cout << str<<"下载完成" << endl;
                //inputFileS<<str<<endl;
            //else
            {
                cout << str<<"下载失败" << endl;
                Sleep(90000);
            }
                //inputFileF<<str<<endl;
        }
    }
    return 0;
    */

    ifstream fin;
    fin.open("纳斯达克.txt");
    ofstream fout;
    fout.open("未提供数据的纳斯达克代码.txt");
    char buff[3000][10];
    int k=0;
    while(fin.good())
    {
        fin.getline(buff[k],10);
        k++;
    }
    fin.close();
    for(int i=0;i<k;i++)
    {
        std::string str = buff[i];
        bR = DownloadUrl("http://real-chart.finance.yahoo.com/table.csv?s="+str+"&d=06&e=01&f=2015&g=d&a=00&b=01&c=2013&ignore=.csv", str+".txt");
        if(!bR)
        {
            cout<<buff[i]<<"下载失败"<<endl;
            fout<<buff[i]<<endl;
            Sleep(90000);
        }
        //else
            //cout << str<<"下载成功" << endl;
    }
    return 0;
}