电脑是否联网

#include <iostream>  
#include <WTypes.h>  
#include <Sensapi.h>  
using namespace std;  
  
#pragma comment(lib,"Sensapi.lib")  
  
  
bool isConnect()  
{  
    DWORD dwFlags;  
    if(IsNetworkAlive(&dwFlags))  
    {  
        if(NETWORK_ALIVE_LAN == dwFlags)  
        {  
            cout<<"One or more LAN"<<endl;  
        }  
        else if(NETWORK_ALIVE_WAN == dwFlags)  
        {  
            cout<<"One or more RAS"<<endl;  
        }  
        else  
        {  
  
        }  
        return true;  
    }  
    else  
    {  
        DWORD dwError = GetLastError();  
        if(ERROR_SUCCESS == dwError)  
        {  
            cout<<"No Connection"<<endl;  
        }  
        else  
        {  
            cout<<"Connection Error"<<endl;  
        }  
        return false;  
    }  

}  

//  *****************************///  三种方法整理。

bool isConnect;  
DWORD dw;  
isConnect = ::IsNetworkAlive(&dw);

if(isConnect)  
　　cout << "IsNetworkAlive连接" <<endl;  
else  
　　cout << "IsNetworkAlive未连接" <<endl;   
cout<< "---------------------------------" <<endl;  

//dw和dw2标识，可判断本机是以什么方式连接网络。如：代理、拨号等

DWORD dw2;  
bool ret = InternetGetConnectedState(&dw2, 0);  
if (ret)  
　　cout << "InternetGetConnectedState连接" <<endl;  
else  
　　cout << "InternetGetConnectedState未连接" <<endl;  
cout<< "**********************************"  <<endl;  
     
//FLAG_ICC_FORCE_CONNECTION不可少；当该网络连接地址链接不通时，该API需ping一段时间(1~2分钟)
      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;