初略網絡連接狀態相關的工具類NetUtils

import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;

public class NetUtils {
    /**
     * 判斷網絡是否連接
     */
    public static boolean isConnected(Context context) {
        ConnectivityManager cm = (ConnectivityManager)
                context.getSystemService(Context.CONNECTIVITY_SERVICE);

        if (null == cm) {
            return false;
        }

        NetworkInfo info = cm.getActiveNetworkInfo();
        if (null != info && info.isConnected()) {
            if (info.getState() == NetworkInfo.State.CONNECTED) {
                return true;
            }
        }
        return false;
    }

    /**
     * 判斷是否是wifi連接
     */
    public static boolean isWifi(Context context) {
        ConnectivityManager cm = (ConnectivityManager)
                context.getSystemService(Context.CONNECTIVITY_SERVICE);

        if (null == cm) {
            return false;
        }

        NetworkInfo info = cm.getActiveNetworkInfo();
        if (null != info) {
            if (info.getType() == ConnectivityManager.TYPE_WIFI) {
                return true;
            }
        }
        return false;

    }

    /**
     * 打開網絡設置界面
     */
    public static void openSetting(Activity activity, int requestCode) {
        try{
            Intent intent = new Intent("/");
            ComponentName cm = new ComponentName("com.android.settings",
                    "com.android.settings.WirelessSettings");
            intent.setComponent(cm);
            intent.setAction(Intent.ACTION_VIEW);
            activity.startActivityForResult(intent, requestCode);
        }catch (Exception e){

        }

    }
}

詳細獲取3G、4G、運營商等：https://blog.csdn.net/NiuAGeNiuC/article/details/91372765