用QT实现Wake On Lan功能（附全部程序源码）

Wake On Lan也就是远程唤醒（远程开机），即通过一台PC向另一台已经关机但仍连接电源PC发送网络数据包，使其开机的功能，前提是两台PC同处一个局域网内，且被唤醒方的网卡支持网络唤醒功能（现在网卡基本上都支持啦）。


原理：PC关闭后，网卡仍能获取电源，一直监听“magic” packet到来，这种数据包可以是IP、IPX或者其它什么，其中封装了特制的字节序列，一旦收到这种数据包，通过网卡与主板的协作，实现远程启动。

Magic包的格式：如果目标主机的MAC地址为 01:02:03:04:05:06的话，包的组成应该如下：

FFFFFFFFFFFF010203040506010203040506010203040506010203040506
010203040506010203040506010203040506010203040506010203040506
010203040506010203040506010203040506010203040506010203040506
010203040506010203040506
由6个16进制字节的FF和至少重复16次MAC地址组成。

下面是在QT3中实现的源代码：


//文件名：main.cpp


#include <qapplication.h>


#include "frmMain.h"




int main( int argc, char ** argv )




...{


QApplication a( argc, argv );


Form1 w;


w.show();


a.connect( &a, SIGNAL( lastWindowClosed() ), &a, SLOT( quit() ) );


return a.exec();


}








/**//****************************************************************************


** Form implementation generated from reading ui file 'frmMain.ui'


**文件名：frmMain.cpp


** Created: 星期四 十月 19 16:30:55 2006


** by: The User Interface Compiler ($Id: qt/main.cpp 3.3.4 edited Nov 24 2003 $)


**


** WARNING! All changes made in this file will be lost!


****************************************************************************/




#include "frmMain.h"




#include <qvariant.h>


#include <qlineedit.h>


#include <qpushbutton.h>


#include <qlayout.h>


#include <qtooltip.h>


#include <qwhatsthis.h>


#include <qaction.h>


#include <qmenubar.h>


#include <qpopupmenu.h>


#include <qtoolbar.h>


#include <qimage.h>


#include <qpixmap.h>




#include "frmMain.ui.h"




/**//*


* Constructs a Form1 as a child of 'parent', with the


* name 'name' and widget flags set to 'f'.


*


*/


Form1::Form1( QWidget* parent, const char* name, WFlags fl )


: QMainWindow( parent, name, fl )




...{


(void)statusBar();


if ( !name )


setName( "Form1" );


setCentralWidget( new QWidget( this, "qt_central_widget" ) );




lineEdit1 = new QLineEdit( centralWidget(), "lineEdit1" );


lineEdit1->setGeometry( QRect( 40, 50, 271, 30 ) );




pushButton2 = new QPushButton( centralWidget(), "pushButton2" );


pushButton2->setGeometry( QRect( 120, 110, 80, 23 ) );




// toolbars




languageChange();


resize( QSize(391, 250).expandedTo(minimumSizeHint()) );


clearWState( WState_Polished );




// signals and slots connections


connect( pushButton2, SIGNAL( clicked() ), this, SLOT( pushButton2_clicked() ) );


}






/**//*


* Destroys the object and frees any allocated resources


*/


Form1::~Form1()




...{


// no need to delete child widgets, Qt does it all for us


}






/**//*


* Sets the strings of the subwidgets using the current


* language.


*/


void Form1::languageChange()




...{


setCaption( tr( "Wake On Lan For QT" ) );


lineEdit1->setText("00-11-09-9C-CF-A2");


pushButton2->setText( trUtf8( "/xe8/xbf/x9c/xe7/xa8/x8b/xe5/xbc/x80/xe6/x9c/xba" ) );


}








/**//****************************************************************************


** Form interface generated from reading ui file 'frmMain.ui'


**文件名：frmMain.h


** Created: 星期四 十月 19 15:44:26 2006


** by: The User Interface Compiler ($Id: qt/main.cpp 3.3.4 edited Nov 24 2003 $)


**


** WARNING! All changes made in this file will be lost!


****************************************************************************/




#ifndef FORM1_H


#define FORM1_H




#include <qvariant.h>


#include <qmainwindow.h>




class QVBoxLayout;


class QHBoxLayout;


class QGridLayout;


class QSpacerItem;


class QAction;


class QActionGroup;


class QToolBar;


class QPopupMenu;


class QLineEdit;


class QPushButton;




class Form1 : public QMainWindow




...{


Q_OBJECT




public:


Form1( QWidget* parent = 0, const char* name = 0, WFlags fl = WType_TopLevel );


~Form1();




QLineEdit* lineEdit1;


QPushButton* pushButton2;




public slots:


virtual void pushButton2_clicked();




protected:




protected slots:


virtual void languageChange();




};




#endif // FORM1_H






/**//****************************************************************************


** ui.h extension file, included from the uic-generated form implementation.


**文件名：frmMain.ui.h


** If you want to add, delete, or rename functions or slots, use


** Qt Designer to update this file, preserving your code.


**


** You should not define a constructor or destructor in this file.


** Instead, write your code in functions called init() and destroy().


** These will automatically be called by the form's constructor and


** destructor.


*****************************************************************************/


#include "qsocketdevice.h"


#include <qcstring.h>


#include <qmessagebox.h>




void Form1::pushButton2_clicked()




...{


//建立套接字相关对象


QSocketDevice *MUReceiveSocket; //套接字对象


//QSocketNotifier *MSocketNotifier; //套接字监听对象


//初始化套接字相关对象


MUReceiveSocket=new QSocketDevice(QSocketDevice::Datagram);


//UDP初始化


QHostAddress MyAddress;


QString FakeAddress;


QString SMacAddr=lineEdit1->text();//网卡的mac地址


const Port=0;//目标机器的端口号




//检查MAC地址是否等于17




if (SMacAddr.length()!=17) ...{


QMessageBox::warning(this,"MAC Address ERR","MAC Address must be =17");


return;


}


//检查MAC地址是否正确




for (int i=2;i<17;i=i+3) ...{




if (SMacAddr[i]!='-') ...{


QMessageBox::warning(this,"MAC Address ERR","MAC Adresse must be like this: 00-D0-4C-BF-52-BA");


return;


}


}




char MACAddr[6];


char MagicPacket[102];//实现远程开机的Magic包




int j=sscanf(SMacAddr, "%2x-%2x-%2x-%2x-%2x-%2x",


&MACAddr[0], &MACAddr[1], &MACAddr[2], &MACAddr[3], &MACAddr[4], &MACAddr[5]);


if (j!=6)




...{


QMessageBox::warning(this,"MAC Address ERR","Invalid MAC Adresse!");


return;


}




//把magicpacket数组前6个字符设置成16进制的ff


memset(MagicPacket, 0xff, 6);




int packetsize=6;//初始值是6，不要搞错了啊。我就是因为大意，把初始会值写成0，实在是太顺手了。


//构建MagicPacket


for (i=0;i<16;i++)




...{


memcpy(MagicPacket+packetsize,MACAddr,6);


packetsize+=6;


}




FakeAddress = "192.168.1.255"; //取得接口IP


MyAddress.setAddress(FakeAddress);


MUReceiveSocket->writeBlock(MagicPacket,102,MyAddress,Port);






}







Main.cpp、frmMain.cpp和frmMain.h是做完界面后QT自动生成的啦，主要的代码编写工作都在frmMain.ui.h。在frmMain.ui.h中实现Magic包的构建，并通过UDP方式将其广播出去。

在QT3中实现UDP网络功能的类是qsocketdevice，见源码。而在QT4中没有这个类，代之的是QUdpSocket,所以这个源码在QT4中无法通过编译。有兴趣的，可以自行修改。源码很简短，并有较详细的注释，我相信大家都能明白。该源码在XP+QT3+VC6中编译通过。

提醒一点的就是在写程序时尽量不要把C++的变量与QT的变量混用，虽然大多时候都能通过编译，但得到的数值并不一定是正确的，而且有时会出错的莫名其妙。我只是个QT的初学都，C++也没学多久，以前一直都是用delphi，有什么错误请大家多指教。