Android通过代码打开和关闭网络连接

我们都知道，要打开网络连接是要有相应的权限的，但是目前Android中并没有直接打开和关闭网络连接的权限，因此我们只能通过APN来实现：

由于Android对于APN的网络API没有公开，不过我们可以阅读源代码，然后进行数据库操作，系统会自动监听数据库的变化，从而实现开启或者关闭APN。

 

其实原理很简单 ：
1 、 当开启APN的时候，设置一个正确的移动或者联通的APN
2、 关闭的时候设置一个错误APN就会自动关闭网络

下面是源代码：

package com.mandr.network.demo;

import java.util.ArrayList;
import java.util.List;

import android.app.Activity;
import android.content.ContentValues;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;

public class OpenNetworkActivity extends Activity {
 private Button open, close;
 Uri uri =Uri.parse("content://telephony/carriers");

 @Override
 public void onCreate(Bundle savedInstanceState){
  super.onCreate(savedInstanceState);
  setContentView(R.layout.main);

  open = (Button)findViewById(R.id.open);
  close = (Button)findViewById(R.id.close);
  open.setOnClickListener(newView.OnClickListener() {

   publicvoid onClick(View v) {
    openAPN();
   }
  });
  close.setOnClickListener(newView.OnClickListener() {

   publicvoid onClick(View v) {
    closeAPN();
   }
  });
 }

 public void openAPN() {
  List list = getAPNList();
  for (APN apn : list) {
   ContentValuescv = new ContentValues();
   cv.put("apn",APNMatchTools.matchAPN(apn.apn));
   cv.put("type",APNMatchTools.matchAPN(apn.type));
   getContentResolver().update(uri,cv, "_id=?",
     newString[] { apn.id });
  }
 }

 public void closeAPN() {
  List list = getAPNList();
  for (APN apn : list) {
   ContentValuescv = new ContentValues();
   cv.put("apn",APNMatchTools.matchAPN(apn.apn) + "mdev");
   cv.put("type",APNMatchTools.matchAPN(apn.type) + "mdev");
   getContentResolver().update(uri,cv, "_id=?",
     newString[] { apn.id });
  }
 }

 private List getAPNList() {
  String tag ="Main.getAPNList()";
  // current不为空表示可以使用的APN
  String projection[] = {"_id,apn,type,current" };
  //查询数据库
  Cursor cr =this.getContentResolver().query(uri, projection, null,
    null,null);
  List list = newArrayList();
  while (cr != null &&cr.moveToNext()) {
   Log.d(tag,
     cr.getString(cr.getColumnIndex("_id"))+ "  "
       +cr.getString(cr.getColumnIndex("apn")) + " "
       +cr.getString(cr.getColumnIndex("type")) + " "
       +cr.getString(cr.getColumnIndex("current")));
   APN a = newAPN();
   a.id =cr.getString(cr.getColumnIndex("_id"));
   a.apn =cr.getString(cr.getColumnIndex("apn"));
   a.type =cr.getString(cr.getColumnIndex("type"));
   list.add(a);
  }
  if (cr != null)
   cr.close();
  return list;
 }

 public static class APN {
  String id;
  String apn;
  String type;
 }

}

APNMatchTools.java
package com.mandr.network.demo;

public class APNMatchTools {
 public static class APNNet {

  public static String CMWAP ="cmwap";

  public static String CMNET ="cmnet";
  // 中国联通3GWAP设置 中国联通3G因特网设置中国联通WAP设置 中国联通因特网设置
  // 3gwap 3gnet uniwapuninet

  public static String GWAP_3= "3gwap";

  public static String GNET_3= "3gnet";

  public static String UNIWAP= "uniwap";

  public static String UNINET= "uninet";
 }

 public static String matchAPN(StringcurrentName) {
  if ("".equals(currentName) ||null == currentName) {
   return"";
  }
  currentName =currentName.toLowerCase();
  if(currentName.startsWith(APNNet.CMNET))
   returnAPNNet.CMNET;
  else if(currentName.startsWith(APNNet.CMWAP))
   returnAPNNet.CMWAP;
  else if(currentName.startsWith(APNNet.GNET_3))
   returnAPNNet.GNET_3;
  else if(currentName.startsWith(APNNet.GWAP_3))
   returnAPNNet.GWAP_3;
  else if(currentName.startsWith(APNNet.UNINET))
   returnAPNNet.UNINET;
  else if(currentName.startsWith(APNNet.UNIWAP))
   returnAPNNet.UNIWAP;
  else if(currentName.startsWith("default"))
   return"default";
  else
   return"";
  // returncurrentName.substring(0, currentName.length() -
  // SUFFIX.length());
 }

}
最后别忘了加入修改APN的权限：