用WinInet远程下载文件的示例代码

#include<windows.h>
#include<wininet.h>
#include<iostream>
#include <tchar.h>
using namespace std;

#pragma comment(lib,"wininet.lib")
void main()
{
DWORD byteread=0;
char buffer[100];
memset(buffer,0,100);
HINTERNET internetopen;

internetopen = InternetOpen(/*_T("DownLoadFile")*/NULL,INTERNET_OPEN_TYPE_DIRECT,NULL,NULL,0);
if (internetopen==NULL)
{
cout<<"Internet open failed!"<<endl;
return;
}

HINTERNET    internetopenurl;
internetopenurl = InternetOpenUrl(internetopen,_T("http://topic.csdn.net/u/20090429/10/6a38f59f-b776-4140-a11b-f59c4a979931.html"),
NULL,0,INTERNET_FLAG_TRANSFER_BINARY|INTERNET_FLAG_PRAGMA_NOCACHE,0);      //下载的URL
if (internetopenurl==NULL)
{
cout<<"Internet open url failed! error code = "<<GetLastError()<<endl;
goto there;
}

BOOL hwrite;
DWORD written;
HANDLE createfile;
createfile = CreateFile(_T("c://downloaded.html"),GENERIC_WRITE,0,0,CREATE_ALWAYS,FILE_ATTRIBUTE_NORMAL,0);  //保存文件
if (createfile==INVALID_HANDLE_VALUE)
{
cout<<"Create File failed!"<<endl;
goto next;
}
BOOL internetreadfile;
while(1)
{
internetreadfile=InternetReadFile(internetopenurl,buffer,sizeof(buffer),&byteread);
if(byteread==0)
break;
hwrite=WriteFile(createfile,buffer,sizeof(buffer),&written,NULL);
if (hwrite==0)
{
cout<<"Write to file failed!"<<endl;
goto here;
}
}
cout<<"Finished downloading!"<<endl;
here:
CloseHandle(createfile);
next:
InternetCloseHandle(internetopenurl);
there:
InternetCloseHandle(internetopen);
}