| 以文本方式查看主題 - 曙海教育集團(tuán)論壇 (http://www.xinguifushi.cn/bbs/index.asp) -- Delphi程序設(shè)計(jì) (http://www.xinguifushi.cn/bbs/list.asp?boardid=76) ---- 用Delphi設(shè)計(jì)代理服務(wù)器設(shè)計(jì)sessioni-1endbeginprocedureTObjectSender: (http://www.xinguifushi.cn/bbs/dispbbs.asp?boardid=76&id=2573) |
| -- 作者：wangxinxin -- 發(fā)布時(shí)間：2010-12-14 11:24:40 -- 用Delphi設(shè)計(jì)代理服務(wù)器設(shè)計(jì)sessioni-1endbeginprocedureTObjectSender: <br>用Delphi設(shè)計(jì)自己的代理服務(wù)器 <br> <br> 筆者在編寫一個(gè)上網(wǎng)計(jì)費(fèi)軟件時(shí)，涉及到如何對(duì)局域網(wǎng)中各工作站上網(wǎng)計(jì)費(fèi)問(wèn)題。一般來(lái)講，這些工作站通過(guò)代理服務(wù)器上網(wǎng)，而采用現(xiàn)成的代理服務(wù)器軟件時(shí)，由于代理服務(wù)器軟件是封閉的系統(tǒng)，很難編寫程序獲取實(shí)時(shí)的上網(wǎng)計(jì)時(shí)信息。因此，考慮是否能編寫自己的代理服務(wù)器，一方面解決群體上網(wǎng)，另一方面又解決上網(wǎng)的計(jì)費(fèi)問(wèn)題呢？ <br> 經(jīng)過(guò)實(shí)驗(yàn)性編程，終于圓滿地解決了該問(wèn)題。現(xiàn)寫出來(lái)，與各位同行分享。 <br> <br>1、思路 <br>當(dāng)前流行的瀏覽器的系統(tǒng)選項(xiàng)中有一個(gè)參數(shù)，即“通過(guò)代理服務(wù)器連接”，經(jīng)過(guò)編程測(cè) <br>試，當(dāng)局域網(wǎng)中一臺(tái)工作站指定了該屬性，再發(fā)出Internet請(qǐng)求時(shí)，請(qǐng)求數(shù)據(jù)將發(fā)送到所指定的代理服務(wù)器上，以下為請(qǐng)求數(shù)據(jù)包示例： <br> GEThttp://home.microsoft.com/intl/cn/HTTP/1.0 <br> Accept:*/* <br> Accept-Language:zh-cn <br> Accept-Encoding:gzip,deflate <br> User-Agent:Mozilla/4.0(compatible;MSIE5.0;WindowsNT) <br> Host:home.microsoft.com <br> Proxy-Connection:Keep-Alive <br>其中第一行為目標(biāo)URL及相關(guān)方法、協(xié)議，“Host”行指定了目標(biāo)主機(jī)的地址。 <br>由此知道了代理服務(wù)的過(guò)程：接收被代理端的請(qǐng)求、連接真正的主機(jī)、接收主機(jī)返回的數(shù)據(jù)、將接收數(shù)據(jù)發(fā)送到被代理端。 <br>為此可編寫一個(gè)簡(jiǎn)單的程序，完成上述網(wǎng)絡(luò)通信重定向問(wèn)題。 <br>用Delphi設(shè)計(jì)時(shí)，選用ServerSocket作為與被代理工作站通信的套接字控件，選用ClientSocket動(dòng)態(tài)數(shù)組作為與遠(yuǎn)程主機(jī)通信的套接字控件。 <br>編程時(shí)應(yīng)解決的一個(gè)重要問(wèn)題是多重連接處理問(wèn)題，為了加快代理服務(wù)的速度和被代理端的響應(yīng)速度，套接字控件的屬性應(yīng)設(shè)為非阻塞型；各通信會(huì)話與套接字動(dòng)態(tài)綁定，用套接字的SocketHandle屬性值確定屬于哪一個(gè)會(huì)話。 <br>通信的銜接過(guò)程如下圖所示： <br> <br> 代理服務(wù)器 <br> <br> Serversocket <br> (1) 接 收 <br> 被代理端 發(fā) 送 遠(yuǎn)程主機(jī) <br> (6) (2) (5) <br> Browser ClientSocket (4) WebServer <br> 接 收 <br> 發(fā) 送 (3) <br> <br> <br>（1）、被代理端瀏覽器發(fā)出Web請(qǐng)求，代理服務(wù)器的Serversocket接收到請(qǐng)求。 <br>（2）、代理服務(wù)器程序自動(dòng)創(chuàng)建一個(gè)ClientSocket，并設(shè)置主機(jī)地址、端口等屬性，然后連接遠(yuǎn)程主機(jī)。 <br>（3）、遠(yuǎn)程連通后激發(fā)發(fā)送事件，將Serversocket接收到的Web請(qǐng)求數(shù)據(jù)包發(fā)送到遠(yuǎn)程主機(jī)。 <br>（4）、當(dāng)遠(yuǎn)程主機(jī)返回頁(yè)面數(shù)據(jù)時(shí)，激發(fā)ClientSocket的讀事件，讀取頁(yè)面數(shù)據(jù)。 <br>（5）、代理服務(wù)器程序根據(jù)綁定信息確定屬于ServerSocket控件中的哪一個(gè)Socket應(yīng)該將從主機(jī)接收的頁(yè)面信息發(fā)送到被代理端。 <br>（6）、ServerSocket中的對(duì)應(yīng)Socket將頁(yè)面數(shù)據(jù)發(fā)送到被代理端。 <br> <br>2、程序編寫 <br>使用Delphi設(shè)計(jì)以上通信過(guò)程非常簡(jiǎn)單，主要是ServerSocket、ClientSocket的相關(guān)事 <br>件驅(qū)動(dòng)程序的程序編寫。下面給出作者編寫的實(shí)驗(yàn)用代理服務(wù)器界面與源程序清單，內(nèi)含簡(jiǎn)要功能說(shuō)明： <br> <br>unitmain; <br> <br>interface <br> <br>uses <br> Windows,Messages,SysUtils,Classes,Graphics,Controls,Forms,Dialogs, <br> ExtCtrls,ScktComp,TrayIcon,Menus,StdCtrls; <br> <br>type <br> session_record=record <br> Used:boolean; <br> SS_Handle:integer; <br> CSocket:TClientSocket; <br> Lookingup:boolean; <br> LookupTime:integer; <br> Request:boolean; <br> request_str:string; <br> client_connected:boolean; <br> remote_connected:boolean; <br>end; <br> <br>type <br> TForm1=class(TForm) <br> ServerSocket1:TServerSocket; <br> ClientSocket1:TClientSocket; <br> Timer2:TTimer; <br> TrayIcon1:TTrayIcon; <br> PopupMenu1:TPopupMenu; <br> N11:TMenuItem; <br> N21:TMenuItem; <br> N1:TMenuItem; <br> N01:TMenuItem; <br> Memo1:TMemo; <br> Edit1:TEdit; <br> Label1:TLabel; <br> Timer1:TTimer; <br> procedureTimer2Timer(Sender:TObject); <br> procedureN11Click(Sender:TObject); <br> procedureFormCreate(Sender:TObject); <br> procedureFormClose(Sender:TObject;varAction:TCloseAction); <br> procedureN21Click(Sender:TObject); <br> procedureN01Click(Sender:TObject); <br> procedureServerSocket1ClientConnect(Sender:TObject; <br> Socket:TCustomWinSocket); <br> procedureServerSocket1ClientDisconnect(Sender:TObject; <br> Socket:TCustomWinSocket); <br> procedureServerSocket1ClientError(Sender:TObject; <br> Socket:TCustomWinSocket;ErrorEvent:TErrorEvent; <br> varErrorCode:Integer); <br> procedureServerSocket1ClientRead(Sender:TObject; <br> Socket:TCustomWinSocket); <br> procedureClientSocket1Connect(Sender:TObject; <br> Socket:TCustomWinSocket); <br> procedureClientSocket1Disconnect(Sender:TObject; <br> Socket:TCustomWinSocket); <br> procedureClientSocket1Error(Sender:TObject;Socket:TCustomWinSocket; <br> ErrorEvent:TErrorEvent;varErrorCode:Integer); <br> procedureClientSocket1Write(Sender:TObject; <br> Socket:TCustomWinSocket); <br> procedureClientSocket1Read(Sender:TObject;Socket:TCustomWinSocket); <br> procedureServerSocket1Listen(Sender:TObject; <br> Socket:TCustomWinSocket); <br> procedureAppException(Sender:TObject;E:Exception); <br> procedureTimer1Timer(Sender:TObject); <br> ** <br> {**declarations} <br> public <br> Service_Enabled:boolean; <br> session:arrayofsession_record; <br> sessions:integer; <br> LookUpTimeOut:integer; <br> I(yíng)nvalidRequests:integer; <br> end; <br> <br>var <br> Form1:TForm1; <br> <br>implementation <br> <br>{$R*.DFM} <br> <br>file://系統(tǒng)啟動(dòng)定時(shí)器，啟動(dòng)窗顯示完成后，縮小到SystemTray… <br>procedureTForm1.Timer2Timer(Sender:TObject); <br>begin <br> timer2.Enabled:=false; <br> sessions:=0; <br> Application.OnException:=AppException; <br> invalidRequests:=0; <br> LookUpTimeOut:=60000; <br> timer1.Enabled:=true; <br> n11.Enabled:=false; <br> n21.Enabled:=true; <br> serversocket1.Port:=988; <br> serversocket1.Active:=true; <br> form1.hide; {隱藏界面，縮小到SystemTray上} <br>end; <br> <br>file://開(kāi)啟服務(wù)菜單項(xiàng)… <br>procedureTForm1.N11Click(Sender:TObject); <br>begin <br> serversocket1.Active:=true; <br>end; <br> <br> <br>file://停止服務(wù)菜單項(xiàng)… <br>procedureTForm1.N21Click(Sender:TObject); <br>begin <br> serversocket1.Active:=false; <br> N11.Enabled:=True; <br> N21.Enabled:=False; <br> Service_Enabled:=false; <br>end; <br> <br> <br>file://主窗口建立… <br>procedureTForm1.FormCreate(Sender:TObject); <br>begin <br> Service_Enabled:=false; <br> timer2.Enabled:=true; <br>end; <br> <br>file://窗口關(guān)閉時(shí)… <br>procedureTForm1.FormClose(Sender:TObject;varAction:TCloseAction); <br>begin <br> timer1.Enabled:=false; <br> ifService_Enabledthen <br> serversocket1.Active:=false; <br>end; <br> <br>file://退出程序按鈕… <br>procedureTForm1.N01Click(Sender:TObject); <br>begin <br> form1.Close; <br>end; <br> <br>file://開(kāi)啟代理服務(wù)后… <br>procedureTForm1.ServerSocket1Listen(Sender:TObject; <br> Socket:TCustomWinSocket); <br>begin <br> Service_Enabled:=true; <br> N11.Enabled:=false; <br> N21.Enabled:=true; <br>end; <br> <br>file://被代理端連接到代理服務(wù)器后，建立一個(gè)會(huì)話，并與套接字綁定… <br>procedureTForm1.ServerSocket1ClientConnect(Sender:TObject; <br> Socket:TCustomWinSocket); <br>var <br>i,j:integer; <br>begin <br> j:=-1; <br> fori:=1tosessionsdo <br> ifnotsession[i-1].Usedandnotsession[i-1].CSocket.activethen <br> begin <br> j:=i-1; <br> session[j].Used:=true; <br> break; <br> end <br> else <br> ifnotsession[i-1].Usedandsession[i-1].CSocket.activethen <br> session[i-1].CSocket.active:=false; <br> ifj=-1then <br> begin <br> j:=sessions; <br> inc(sessions); <br> setlength(session,sessions); <br> session[j].Used:=true; <br> session[j].CSocket:=TClientSocket.Create(nil); <br> session[j].CSocket.OnConnect:=ClientSocket1Connect; <br> session[j].CSocket.OnDisconnect:=ClientSocket1Disconnect; <br> session[j].CSocket.OnError:=ClientSocket1Error; <br> session[j].CSocket.OnRead:=ClientSocket1Read; <br> session[j].CSocket.OnWrite:=ClientSocket1Write; <br> session[j].Lookingup:=false; <br> end; <br> session[j].SS_Handle:=socket.socketHandle; <br> session[j].Request:=false; <br> session[j].client_connected:=true; <br> session[j].remote_connected:=false; <br> edit1.text:=inttostr(sessions); <br>end; <br> <br>file://被代理端斷開(kāi)時(shí)… <br>procedureTForm1.ServerSocket1ClientDisconnect(Sender:TObject; <br> Socket:TCustomWinSocket); <br>var <br>i,j,k:integer; <br>begin <br> fori:=1tosessionsdo <br> if(session[i-1].SS_Handle=socket.SocketHandle)andsession[i-1].Usedthen <br> begin <br> session[i-1].client_connected:=false; <br> ifsession[i-1].remote_connectedthen <br> session[i-1].CSocket.active:=false <br> else <br> session[i-1].Used:=false; <br> break; <br> end; <br> j:=sessions; <br> k:=0; <br> fori:=1tojdo <br> begin <br> ifsession[j-i].Usedthen <br> break; <br> inc(k); <br> end; <br> ifk%26gt;0then <br> begin <br> sessions:=sessions-k; <br> setlength(session,sessions); <br> end; <br> edit1.text:=inttostr(sessions); <br>end; <br> <br>file://通信錯(cuò)誤出現(xiàn)時(shí)… <br>procedureTForm1.ServerSocket1ClientError(Sender:TObject; <br> Socket:TCustomWinSocket;ErrorEvent:TErrorEvent; <br> varErrorCode:Integer); <br>var <br>i,j,k:integer; <br>begin <br> fori:=1tosessionsdo <br> if(session[i-1].SS_Handle=socket.SocketHandle)andsession[i-1].Usedthen <br> begin <br> session[i-1].client_connected:=false; <br> ifsession[i-1].remote_connectedthen <br> session[i-1].CSocket.active:=false <br> else <br> session[i-1].Used:=false; <br> break; <br> end; <br> j:=sessions; <br> k:=0; <br> fori:=1tojdo <br> begin <br> ifsession[j-i].Usedthen <br> break; <br> inc(k); <br> end; <br> ifk%26gt;0then <br> begin <br> sessions:=sessions-k; <br> setlength(session,sessions); <br> end; <br> edit1.text:=inttostr(sessions); <br> errorcode:=0; <br>end; <br> <br>file://被代理端發(fā)送來(lái)頁(yè)面請(qǐng)求時(shí)… <br>procedureTForm1.ServerSocket1ClientRead(Sender:TObject; <br> Socket:TCustomWinSocket); <br>var <br>tmp,line,host:string; <br>i,j,port:integer; <br>begin <br> fori:=1tosessionsdo <br> ifsession[i-1].Usedand(session[i-1].SS_Handle=socket.sockethandle)then <br> begin <br> session[i-1].request_str:=socket.ReceiveText; <br> tmp:=session[i-1].request_str; <br> memo1.lines.add(tmp); <br> j:=pos(char(13)+char(10),tmp); <br> whilej%26gt;0do <br> begin <br> line:=copy(tmp,1,j-1); <br> delete(tmp,1,j+1); <br> j:=pos(\'Host\',line); <br> ifj%26gt;0then <br> begin <br> delete(line,1,j+5); <br> j:=pos(\':\',line); <br> ifj%26gt;0then <br> begin <br> host:=copy(line,1,j-1); <br> delete(line,1,j); <br> try <br> port:=strtoint(line); <br> except <br> port:=80; <br> end; <br> end <br> else <br> begin <br> host:=trim(line); <br> port:=80; <br> end; <br> ifnotsession[i-1].remote_connectedthen <br> begin <br> session[i-1].Request:=true; |