一、需要权限：

    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />           <uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />           <uses-permission android:name="android.permission.MODIFY_PHONE_STATE" />  

二、下面代码实现功能、如果gprs已经打开则先关闭再打开、否则直接打开、

    package com.example.gprstoggle;                import java.lang.reflect.Method;                import android.app.Activity;        import android.content.Context;        import android.net.ConnectivityManager;        import android.os.Bundle;                public class MainActivity extends Activity {                    private ConnectivityManager mCM;             @Override            protected void onCreate(Bundle savedInstanceState) {                super.onCreate(savedInstanceState);                setContentView(R.layout.activity_main);                init();            }                    private void init() {                mCM = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);                  gprsSetter();                finish();                            }            //打开或关闭GPRS            private boolean gprsEnabled(boolean bEnable)              {                  Object[] argObjects = null;                                            boolean isOpen = this.gprsIsOpenMethod("getMobileDataEnabled");                  if(isOpen == !bEnable)                  {                      setGprsEnabled("setMobileDataEnabled", bEnable);                  }                                   return isOpen;                }              //打开或关闭GPRS                private boolean gprsSetter()                  {                      Object[] argObjects = null;                                                    boolean isOpen = this.gprsIsOpenMethod("getMobileDataEnabled");                      if(isOpen)                      {                          setGprsEnabled("setMobileDataEnabled", false);                         System.out.println("关闭");                        try {                            Thread.sleep(2000);                        } catch (InterruptedException e) {                            e.printStackTrace();                        }                        setGprsEnabled("setMobileDataEnabled", true);                        System.out.println("开启");                    }else{                        setGprsEnabled("setMobileDataEnabled", true);                        System.out.println("开启");                    }                                          return isOpen;                    }             //检测GPRS是否打开               private boolean gprsIsOpenMethod(String methodName)              {                  Class cmClass       = mCM.getClass();                  Class[] argClasses  = null;                  Object[] argObject  = null;                                    Boolean isOpen = false;                  try                  {                      Method method = cmClass.getMethod(methodName, argClasses);                                isOpen = (Boolean) method.invoke(mCM, argObject);                  } catch (Exception e)                  {                      e.printStackTrace();                  }                            return isOpen;              }                      //开启/关闭GPRS               private void setGprsEnabled(String methodName, boolean isEnable)              {                  Class cmClass       = mCM.getClass();                  Class[] argClasses  = new Class[1];                  argClasses[0]       = boolean.class;                                    try                  {                      Method method = cmClass.getMethod(methodName, argClasses);                      method.invoke(mCM, isEnable);                  } catch (Exception e)                  {                      e.printStackTrace();                  }              }                  }