android 网络判断的几种方法

Android网络判断很简单，看代码就能明白

package mark.zhang;  
  
import java.util.List;  
  
import android.content.Context;  
import android.location.LocationManager;  
import android.net.ConnectivityManager;  
import android.net.NetworkInfo;  
import android.telephony.TelephonyManager;  
  
public class NetworkProber {  
  
    /** 
     * 网络是否可用 
     *  
     * @param activity 
     * @return 
     */  
    public static boolean isNetworkAvailable(Context context) {  
        ConnectivityManager connectivity = (ConnectivityManager) context  
                .getSystemService(Context.CONNECTIVITY_SERVICE);  
        if (connectivity == null) {  
        } else {  
            NetworkInfo[] info = connectivity.getAllNetworkInfo();  
            if (info != null) {  
                for (int i = 0; i < info.length; i++) {  
                    if (info[i].getState() == NetworkInfo.State.CONNECTED) {  
                        return true;  
                    }  
                }  
            }  
        }  
        return false;  
    }  
  
    /** 
     * Gps是否打开 
     *  
     * @param context 
     * @return 
     */  
    public static boolean isGpsEnabled(Context context) {  
        LocationManager locationManager = ((LocationManager) context  
                .getSystemService(Context.LOCATION_SERVICE));  
        List<String> accessibleProviders = locationManager.getProviders(true);  
        return accessibleProviders != null && accessibleProviders.size() > 0;  
    }  
  
    /** 
     * wifi是否打开 
     */  
    public static boolean isWifiEnabled(Context context) {  
        ConnectivityManager mgrConn = (ConnectivityManager) context  
                .getSystemService(Context.CONNECTIVITY_SERVICE);  
        TelephonyManager mgrTel = (TelephonyManager) context  
                .getSystemService(Context.TELEPHONY_SERVICE);  
        return ((mgrConn.getActiveNetworkInfo() != null && mgrConn  
                .getActiveNetworkInfo().getState() == NetworkInfo.State.CONNECTED) || mgrTel  
                .getNetworkType() == TelephonyManager.NETWORK_TYPE_UMTS);  
    }  
  
    /** 
     * 判断当前网络是否是wifi网络 
     * if(activeNetInfo.getType()==ConnectivityManager.TYPE_MOBILE) { //判断3G网 
     *  
     * @param context 
     * @return boolean 
     */  
    public static boolean isWifi(Context context) {  
        ConnectivityManager connectivityManager = (ConnectivityManager) context  
                .getSystemService(Context.CONNECTIVITY_SERVICE);  
        NetworkInfo activeNetInfo = connectivityManager.getActiveNetworkInfo();  
        if (activeNetInfo != null  
                && activeNetInfo.getType() == ConnectivityManager.TYPE_WIFI) {  
            return true;  
        }  
        return false;  
    }  
  
    /** 
     * 判断当前网络是否是3G网络 
     *  
     * @param context 
     * @return boolean 
     */  
    public static boolean is3G(Context context) {  
        ConnectivityManager connectivityManager = (ConnectivityManager) context  
                .getSystemService(Context.CONNECTIVITY_SERVICE);  
        NetworkInfo activeNetInfo = connectivityManager.getActiveNetworkInfo();  
        if (activeNetInfo != null  
                && activeNetInfo.getType() == ConnectivityManager.TYPE_MOBILE) {  
            return true;  
        }  
        return false;  
    }  
}  

另外还有两个方法判断网络是否可用：

public static boolean isNetworkAvailable_00(Context context) {  
        ConnectivityManager cm = ((ConnectivityManager) context  
                .getSystemService(Context.CONNECTIVITY_SERVICE));  
        if (cm != null) {  
            NetworkInfo info = cm.getActiveNetworkInfo();  
            if (info != null && info.isConnectedOrConnecting()) {  
                return true;  
            }  
        }  
        return false;  
    }  
  
    public static boolean isNetworkAvailable_01(Context context) {  
        ConnectivityManager cm = (ConnectivityManager) context  
                .getSystemService(Context.CONNECTIVITY_SERVICE);  
        NetworkInfo network = cm.getActiveNetworkInfo();  
        if (network != null) {  
            return network.isAvailable();  
        }  
        return false;  
    }  

更加严谨的写法：

public static boolean checkNet(Context context) {  
          
        try {  
            ConnectivityManager connectivity = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);  
            if (connectivity != null) {  
              
                NetworkInfo info = connectivity.getActiveNetworkInfo();  
                if (info != null && info.isConnected()) {  
                  
                    if (info.getState() == NetworkInfo.State.CONNECTED) {  
                        return true;  
                    }  
                }  
            }  
        } catch (Exception e) {  
        return false;  
}  
        return false;  
    }  

在这里感谢原作者的总结 ，原文出处：http://blog.csdn.net/veryitman/article/details/6860146