1 INT GetFile(const CString strUrl,const CString strSavePath)
 2 {
 3     //检查传入的两个参数
 4     if (strUrl.IsEmpty())
 5         return -5;
 6     if (strSavePath.IsEmpty())
 7         return -6;
 8
 9     unsigned short nPort;        //用于保存目标HTTP服务端口
10     CString strServer, strObject;    //strServer用于保存服务器地址，strObject用于保存文件对象名称
11     DWORD dwServiceType,dwRet;        //dwServiceType用于保存服务类型，dwRet用于保存提交GET请求返回的状态号
12
13     //解析URL，获取信息
14     if(!AfxParseURL(strUrl, dwServiceType, strServer, strObject, nPort))
15     {
16         //解析失败，该Url不正确
17         return -1;
18     }
19     //创建网络连接对象，HTTP连接对象指针和用于该连接的HttpFile文件对象指针，注意delete
20     CInternetSession intsess;
21     CHttpFile *pHtFile = NULL;
22     //建立网络连接
23     CHttpConnection *pHtCon = intsess.GetHttpConnection(strServer,nPort);
24     if(pHtCon == NULL)
25     {
26         //建立网络连接失败
27         intsess.Close();
28         return -2;
29     }
30     //发起GET请求
31     pHtFile = pHtCon->OpenRequest(CHttpConnection::HTTP_VERB_GET,strObject);
32     if(pHtFile == NULL)
33     {
34         //发起GET请求失败
35         intsess.Close();
36         delete pHtCon;pHtCon = NULL;
37         return -3;
38     }
39     //提交请求
40     pHtFile->SendRequest();
41     //获取服务器返回的状态号
42     pHtFile->QueryInfoStatusCode(dwRet);
43     if (dwRet != HTTP_STATUS_OK)
44     {
45         //服务器不接受请求
46         intsess.Close();
47         delete pHtCon;pHtCon = NULL;
48         delete pHtFile;pHtFile = NULL;
49         return -4;
50     }
51     //获取文件大小
52     UINT nFileLen = (UINT)pHtFile->GetLength();
53     DWORD dwRead = 1;        //用于标识读了多少，为1是为了进入循环
54     //创建缓冲区
55     CHAR *szBuffer = new CHAR[nFileLen+1];
56     TRY
57     {
58         //创建文件
59         CFile PicFile(strSavePath,CFile::modeCreate|CFile::modeWrite|CFile::shareExclusive);
60         while(dwRead>0)
61         {
62             //清空缓冲区
63             memset(szBuffer,0,(size_t)(nFileLen+1));
64             //读取到缓冲区
65             dwRead = pHtFile->Read(szBuffer,nFileLen);
66             //写入到文件
67             PicFile.Write(szBuffer,dwRead);
68         }
69         //关闭文件
70         PicFile.Close();
71         //释放内存
72         delete []szBuffer;
73         delete pHtFile;
74         delete pHtCon;
75         //关闭网络连接
76         intsess.Close();
77     }
78     CATCH(CFileException,e)
79     {
80         //释放内存
81         delete []szBuffer;
82         delete pHtFile;
83         delete pHtCon;
84         //关闭网络连接
85         intsess.Close();
86         return -7;            //读写文件异常
87     }
88     END_CATCH
89         return 0;
90 }