获取系统的网络状态与无线网的信号强度

bool InternetGetConnectedState( out LPDWORD lpdwFlags, int dwReversed);

//声明外部的函数
[DllImport("winInet.dll ")]
private static extern bool InternetGetConnectedState(ref int flag,int dwReserved);

1 var isConnectedNetwork = InternetGetConnectedState(ref Flag, 0);
2 var hasWlan = (Flag & INTERNET_CONNECTION_LAN) != 0;

 1 /// <summary>
 2 /// 网络状态
 3 /// </summary>
 4 public enum NetworkStatus
 5 {
 6     Internet,
 7     InternetWithError,
 8     WifiWithError,
 9     WifiWithOneBar,
10     WifiWithTwoBars,
11     WifiWithThreeBars,
12     WifiWithFourBars,
13 }

 1 //获取网络状态
 2 public static NetworkStatus GetNetworkStatus()
 3 {
 4     var networkStatus = NetworkStatus.InternetWithError;
 5 
 6     int Flag = 0;
 7     var isConnectedNetwork = InternetGetConnectedState(ref Flag, 0);
 8     var hasWlan = (Flag & INTERNET_CONNECTION_LAN) != 0;
 9 
10     if (hasWlan)
11     {
12         var wlanStatus = GetWlanStatus();
13         if (isConnectedNetwork && wlanStatus == NetworkStatus.WifiWithError)
14         {
15             //如未已连接网络，且无线网连接错误，则返回有线网连接正常状态。
16             networkStatus = NetworkStatus.Internet;
17         }
18         else
19         {
20             networkStatus = wlanStatus;
21         }
22     }
23     else
24     {
25         //返回有线网连接状态
26         networkStatus = isConnectedNetwork ? NetworkStatus.Internet : NetworkStatus.InternetWithError;
27     }
28     return networkStatus;
29 } 
31 
32 private static NetworkStatus GetWlanStatus()
33 {
34     var wlanStatus = NetworkStatus.WifiWithError;
35     try
36     {
37         WlanClient wlanClient = new WlanClient();
38 
39         foreach (WlanClient.WlanInterface wlanIface in wlanClient.Interfaces)
40         {
41             if (wlanIface.InterfaceState == Wlan.WlanInterfaceState.Connected && wlanIface.CurrentConnection.isState == Wlan.WlanInterfaceState.Connected)
42             {
43                 Wlan.WlanAvailableNetwork[] networks = wlanIface.GetAvailableNetworkList(0);
44                 foreach (var network in networks)
45                 {
46                     if (network.profileName == wlanIface.CurrentConnection.profileName
47                         && (int)network.flags == (int)(Wlan.WlanAvailableNetworkFlags.Connected | Wlan.WlanAvailableNetworkFlags.HasProfile))
48                     {
49                         switch (network.wlanSignalQuality / 25)
50                         {
51                             case 0:
52                                 wlanStatus = NetworkStatus.WifiWithOneBar;
53                                 break;
54                             case 1:
55                                 wlanStatus = NetworkStatus.WifiWithTwoBars;
56                                 break;
57                             case 2:
58                                 wlanStatus = NetworkStatus.WifiWithThreeBars;
59                                 break;
60                             default:
61                                 wlanStatus = NetworkStatus.WifiWithFourBars;
62                                 break;
63                         } 
65                         break;
66                     }
67                 }
68                 break;
69             }
70         }
71     }
72     catch (Exception e)
73     {
74         Console.WriteLine("获取无线网配置失败！");
75     } 
77     return wlanStatus;
78 }
79 
80 private const int INTERNET_CONNECTION_LAN = 2;
81 
82 //声明外部的函数
83 [DllImport("winInet.dll ")]
84 private static extern bool InternetGetConnectedState(ref int flag, int dwReserved);