vc 网络连接的测试方法

 //
 #include "stdafx.h"
 #include "windows.h"
 #include <Sensapi.h>
 #include <iostream>
 #include <Wininet.h>

 #pragma comment(lib, "Sensapi.lib")
 #pragma comment(lib, "Wininet.lib")

 using namespace  std;

 int _tmain(int argc, TCHAR* argv[], TCHAR* envp[])
 {
     BOOL isConnect;
     DWORD dw;
     isConnect = ::IsNetworkAlive( &dw );
     while (1)
     {
         if(isConnect)
             cout << "IsNetworkAlive连接" <<endl;
         else
             cout << "IsNetworkAlive未连接" <<endl;
         cout<< "---------------------------------" <<endl;



         DWORD dw2;
         BOOL ret = InternetGetConnectedState(&dw2, 0);
         if (ret)
             cout << "InternetGetConnectedState连接" <<endl;
         else
             cout << "InternetGetConnectedState未连接" <<endl;
         cout<< "**********************************"  <<endl;


         BOOL bConnected = InternetCheckConnection(_T("http://www.baidu.com"), FLAG_ICC_FORCE_CONNECTION, 0);
         if (bConnected)
             cout << "InternetCheckConnection连接" <<endl;
         else
             cout << "InternetCheckConnection未连接" <<endl;
         cout<< "%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%"  <<endl;

         //IsDestinationReachable(_T("http://www.google.com"), )


         cout<<endl<<endl<<endl;
         Sleep(1000);

     }
     getchar();
     return 1;
 }