[C#]判断计算机是否处于连网(联网)状态

C#实现判断计算机是否处于连网（联网）状态

if ( SystemInformation.Network )    
  
{      
    MessageBox.Show("该计算机已经联网");      
}      
else   
  
{          
 MessageBox.Show("该计算机尚未联网");      
}

C#实现获取电脑的IP地址

方法1

/// <summary>   
/// 获得IP地址   
/// </summary>   
/// <returns>string类型的IP地址</returns>   
public string GetIPAddress()   
{       
    string text = string.Empty;       
    string result;       
    try      
    {           
        IPAddress[] addressList = Dns.GetHostEntry(Dns.GetHostName()).AddressList;           
        IPAddress[] array = addressList;           
        for (int i = 0; i < array.Length; i++)           
        {               
            IPAddress iPAddress = array[i];               
            if (!iPAddress.IsIPv6SiteLocal)               
            {                   
                text = iPAddress.ToString();              
             }           
        }           
       if (string.IsNullOrEmpty(text))           
       {               
            throw new Exception("Can not get this computer ip address.");          
       }           
       result = text;       
   }       
   catch (Exception ex)       
   {           
       throw new Exception("GetIPAddress Exception: " + ex.Message);      
    }       
    return result;   
}

方法2

public void GetIPAddress(ref string host,ref string ip)   
{       
    try      
    {           
        host = Dns.GetHostName().ToUpper();           
        IPAddress[] addressList = Dns.GetHostEntry(Dns.GetHostName()).AddressList;           
        IPAddress[] array = addressList;           
        for (int i = 0; i < array.Length; i++)           
        {               
            IPAddress iPAddress = array[i];               
            if (!iPAddress.IsIPv6SiteLocal)               
            {                       
                ip = iPAddress.ToString();               
            }           
        }           
        if (string.IsNullOrEmpty(host))           
        {               
            throw new Exception("Can not get this computer name.");           
        }           
        if (string.IsNullOrEmpty(ip))           
        {               
            throw new Exception("Can not get this computer ip address.");           
        }       
    }       
    catch(Exception ex)       
    {           
        throw new Exception("GetIPAddress Exception:" + ex.Message);       
    }   
}