c++编程 实现下载文件

 1 下载文件要用到操作系统的API函数，下面是一个WINDOWS系统中的实现：
 2 
 3 //---------------------------------------------------------------------------
 4 
 5 #include <stdio.h>
 6 #include <windows.h>
 7 #include <wininet.h>
 8 #define MAXBLOCKSIZE 1024
 9 #pragma comment( lib, "wininet.lib" ) ;
10 
11 void download(const char *Url,const char *save_as)/*将Url指向的地址的文件下载到save_as指向的本地文件*/
12 {
13   byte Temp[MAXBLOCKSIZE];
14    ULONG Number = 1;
15 
16    FILE *stream;
17    HINTERNET hSession = InternetOpen((LPCWSTR)"RookIE/1.0", INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
18  if (hSession != NULL)
19  {
20   HINTERNET handle2 = InternetOpenUrl(hSession, (LPCWSTR)Url, NULL, 0, INTERNET_FLAG_DONT_CACHE, 0);
21   if (handle2 != NULL)
22   {
23   
24   
25    if( (stream = fopen( save_as, "wb" )) != NULL )
26    {
27     while (Number > 0)
28     {
29      InternetReadFile(handle2, Temp, MAXBLOCKSIZE - 1, &Number);
30      
31      fwrite(Temp, sizeof (char), Number , stream);
32     }
33     fclose( stream );
34    }
35    
36    InternetCloseHandle(handle2);
37    handle2 = NULL;
38   }
39   InternetCloseHandle(hSession);
40   hSession = NULL;
41  }
42 }
43 
44 int main(int argc, char* argv[]){
45 
46  download("http://www.baidu.com/","c:\\index.html");/*调用示例，下载百度的首页到c:\index.html文件*/
47  return 0;
48 }

以上，转自：http://zhidao.baidu.com/question/126310723.html

 

转载于:https://www.cnblogs.com/wang200/archive/2011/11/20/2256116.html