网络判断

public class NetUtil {
    public  static  boolean isNetWork(Context context)
    {
        ConnectivityManager manager = (ConnectivityManager) context.getSystemService(context.CONNECTIVITY_SERVICE);
        NetworkInfo info = manager.getActiveNetworkInfo();
        if (info!=null)
        {
            return info.isAvailable();
        }
        return false;
    }
}