用InternetOpen（）的下载者

#include<windows.h>
#include<wininet.h>
#include<iostream.h>
#pragma comment(lib,"wininet.lib")
void main()
{
DWORD byteread=0;
char buffer[100];
memset(buffer,0,100);
HINTERNET internetopen;
internetopen=InternetOpen("Testing",INTERNET_OPEN_TYPE_PRECONFIG,NULL,NULL,0);
if (internetopen==NULL){
   cout<<"Internet open failed!"<<endl;
return;}
HINTERNET internetopenurl;
internetopenurl=InternetOpenUrl(internetopen,"http://www.saishuo.com/s.exe",NULL,0,INTERNET_FLAG_RELOAD,0);
     if (internetopenurl==NULL){
   cout<<"Internet open url failed!"<<endl;
   goto there;}

BOOL hwrite;
DWORD written;
HANDLE createfile;
createfile=CreateFile("c:\\sss.exe",GENERIC_WRITE,0,0,CREATE_ALWAYS,FILE_ATTRIBUTE_NORMAL,0);
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);