delphi 7 TServerSocket和TClientSocket兩個組件

筆者在工作中遇到對局域網中各工作站與服務器之間進行Socket通信的問題。現在將本人總結出來的TServerSocket和TClientSocket兩個組件的基本用法寫出來，希望與您分享。 

ClientSocket組件為客戶端組件。它是通信的請求方，也就是說，它是主動地與服務器端建立連接。 

ServerSocket組件為服務器端組件。它是通信的響應方，也就是說，它的動作是監聽以及被動接受客戶端的連接請求，並對請求進行回複。 

ServerSocket組件可以同時接受一個或多個ClientSocket組件的連接請求，並與每個ClientSocket組件建立單獨的連接，進行單獨的通信。因此，一個服務器端可以為多個客戶端服務。 

設計思路 

本例包括一個服務器端程序和一個客戶端程序。客戶端程序可以放到多個計算機上運行，同時與服務器端進行連接通信。 

本例的重點，一是演示客戶端與服務器端如何通信；二是當有多個客戶端同時連接到服務器端時，服務器端如何識別每個客戶端，並對請求給出相應的回複。為了保證一個客戶端斷開連接時不影響其它客戶端與服務器端的通信，同時保證服務器端能夠正確回複客戶端的請求，在本例中聲明了一個記錄類型： 

type 

client_record=record 

CHandle: integer; //客戶端套接字句柄 

CSocket:TCustomWinSocket; //客戶端套接字 

CName:string; //客戶端計算機名稱 

CAddress:string; //客戶端計算機IP地址 

CUsed: boolean; //客戶端聯機標誌 

end; 

利用這個記錄類型數據保存客戶端的信息，同時保存當前客戶端的連接狀態。其中，CHandle保存客戶端套接字句柄，以便準確定位每個與服務器端保持連接的客戶端；Csocket保存客戶端套接字，通過它可以對客戶端進行回複。Cused記錄當前客戶端是否與服務器端保持連接。 

下麵對組件ServerSocket和ClientSocket的屬性設置簡單說明

ServerSocket的屬性： 

· Port，是通信的端口，必須設置。在本例中設置為1025； 

· ServerTypt，服務器端讀寫信息類型，設置為stNonBlocking表示異步讀寫信息，本例中采用這種方式。 

· ThreadCacheSize，客戶端的最大連接數，就是服務器端最多允許多少客戶端同時連接。本例采用默認值10。 

其它屬性采用默認設置即可。 

ClientSocket的屬性： 

· Port，是通信的端口，必須與服務器端的設置相同。在本例中設置為1025； 

· ClientType，客戶端讀寫信息類型，應該與服務器端的設置相同，為stNonBlocking表示異步讀寫信息。 

· Host，客戶端要連接的服務器的IP地址。必須設置，當然也可以在代碼中動態設置。 

其它屬性采用默認設置即可。 

程序源代碼: 

· 服務器端源碼（uServerMain.pas）： 

unit uServerMain; 

interface 

uses 

Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, 

ScktComp, ToolWin, ComCtrls, ExtCtrls, StdCtrls, Buttons; 

const 

CMax=10; //客戶端最大連接數 

type 

client_record=record 

CHandle: integer; //客戶端套接字句柄 

CSocket:TCustomWinSocket; //客戶端套接字 

CName:string; //客戶端計算機名稱 

CAddress:string; //客戶端計算機IP地址 

CUsed: boolean; //客戶端聯機標誌 

end; 

type 

TfrmServerMain = class(TForm) 

ServerSocket: TServerSocket; 

ControlBar1: TControlBar; 

ToolBar1: TToolBar; 

tbConnect: TToolButton; 

tbClose: TToolButton; 

tbDisconnected: TToolButton; 

Edit1: TEdit; 

Memo1: TMemo; 

StatusBar: TStatusBar; 

procedure tbConnectClick(Sender: TObject); 

procedure tbDisconnectedClick(Sender: TObject); 

procedure ServerSocketClientRead(Sender: TObject; 

Socket: TCustomWinSocket); 

procedure ServerSocketListen(Sender: TObject; 

Socket: TCustomWinSocket); 

procedure ServerSocketClientConnect(Sender: TObject; 

Socket: TCustomWinSocket); 

procedure ServerSocketClientDisconnect(Sender: TObject; 

Socket: TCustomWinSocket); 

procedure tbCloseClick(Sender: TObject); 

procedure FormCreate(Sender: TObject); 

procedure FormClose(Sender: TObject; var Action: TCloseAction); 

procedure ServerSocketGetSocket(Sender: TObject; Socket: Integer; 

var ClientSocket: TServerClientWinSocket); 

procedure ServerSocketClientError(Sender: TObject; 

Socket: TCustomWinSocket; ErrorEvent: TErrorEvent; 

var ErrorCode: Integer); 

private 

{ Private declarations } 

public 

{ Public declarations } 

session: array[0..CMax] of client_record; //客戶端連接數組 

Sessions: integer; //客戶端連接數 

end; 

var 

frmServerMain: TfrmServerMain; 

implementation 

{$R *.DFM} 

//打開套接字連接，並使套接字進入監聽狀態 

procedure TfrmServerMain.tbConnectClick(Sender: TObject); 

begin 

ServerSocket.Open ; 

end; 

//關閉套接字連接，不再監聽客戶端的請求 

procedure TfrmServerMain.tbDisconnectedClick(Sender: TObject); 

begin 

ServerSocket.Close; 

StatusBar.Panels[0].Text :='服務器套接字連接已經關閉，無法接受客戶端的連接請求.'; 

end; 

//從客戶端讀取信息 

procedure TfrmServerMain.ServerSocketClientRead(Sender: TObject; 

Socket: TCustomWinSocket); 

var 

i:integer; 

begin 

//將從客戶端讀取的信息添加到Memo1中 

Memo1.Lines.Add(Socket.ReceiveText); 

for i:=0 to sessions do 

begin 

//取得匹配的客戶端 

if session[i].CHandle = Socket.SocketHandle then 

begin 

session[i].CSocket.SendText('回複客戶端'+session[i].CAddress+' ==> '+Edit1.Text); 

end; 

end; 

end; 

//服務器端套接字進入監聽狀態，以便監聽客戶端的連接 

procedure TfrmServerMain.ServerSocketListen(Sender: TObject; 

Socket: TCustomWinSocket); 

begin 

StatusBar.Panels[0].Text :='等待客戶端連接...'; 

end; 

//當客戶端連接到服務器端以後 

procedure TfrmServerMain.ServerSocketClientConnect(Sender: TObject; 

Socket: TCustomWinSocket); 

var 

i,j:integer; 

begin 

j:=-1; 

for i:=0 to sessions do 

begin 

//在原有的客戶端連接數組中有中斷的客戶端連接 

if not session[i].CUsed then 

begin 

session[i].CHandle := Socket.SocketHandle ;//客戶端套接字句柄 

session[i].CSocket := Socket; //客戶端套接字 

session[i].CName := Socket.RemoteHost ; //客戶端計算機名稱 

session[i].CAddress := Socket.RemoteAddress ;//客戶端計算機IP 

session[i].CUsed := True; //連接數組當前位置已經占用 

Break; 

end; 

j:=i; 

end; 

if j=sessions then 

begin 

inc(sessions); 

session[j].CHandle := Socket.SocketHandle ; 

session[j].CSocket := Socket; 

session[j].CName := Socket.RemoteHost ; 

session[j].CAddress := Socket.RemoteAddress ; 

session[j].CUsed := True; 

end; 

StatusBar.Panels[0].Text := '客戶端 '+Socket.RemoteHost + ' 已經連接'; 

end; 

//當客戶端斷開連接時 

procedure TfrmServerMain.ServerSocketClientDisconnect(Sender: TObject; 

Socket: TCustomWinSocket); 

var 

i:integer; 

begin 

for i:=0 to sessions do 

begin 

if session[i].CHandle =Socket.SocketHandle then 

begin 

session[i].CHandle :=0; 

session[i].CUsed := False; 

Break; 

end; 

end; 

StatusBar.Panels[0].Text :='客戶端 '+Socket.RemoteHost + ' 已經斷開'; 

end; 

//關閉窗口 

procedure TfrmServerMain.tbCloseClick(Sender: TObject); 

begin 

Close; 

end; 

procedure TfrmServerMain.FormCreate(Sender: TObject); 

begin 

sessions := 0; 

end; 

procedure TfrmServerMain.FormClose(Sender: TObject; 

var Action: TCloseAction); 

begin 

ServerSocket.Close ; 

end; 

//當客戶端正在與服務器端連接時 

procedure TfrmServerMain.ServerSocketGetSocket(Sender: TObject; 

Socket: Integer; var ClientSocket: TServerClientWinSocket); 

begin 

StatusBar.Panels[0].Text :='客戶端正在連接...'; 

end; 

//客戶端發生錯誤 

procedure TfrmServerMain.ServerSocketClientError(Sender: TObject; 

Socket: TCustomWinSocket; ErrorEvent: TErrorEvent; 

var ErrorCode: Integer); 

begin 

StatusBar.Panels[0].Text :='客戶端'+Socket.RemoteHost +'發生錯誤！'; 

ErrorCode := 0; 

end; 

end. 

· 客戶端源碼(uClientMain.pas)： 

unit uClientMain; 

interface 

uses 

Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, 

ScktComp, ComCtrls, ToolWin, ExtCtrls, StdCtrls, Buttons; 

const 

SocketHost = '172.16.1.6'; //服務器端地址 

type 

TfrmClientMain = class(TForm) 

ControlBar1: TControlBar; 

ToolBar1: TToolBar; 

tbConnected: TToolButton; 

tbSend: TToolButton; 

tbClose: TToolButton; 

tbDisconnected: TToolButton; 

ClientSocket: TClientSocket; 

Edit1: TEdit; 

Memo1: TMemo; 

StatusBar: TStatusBar; 

btnSend: TBitBtn; 

procedure tbConnectedClick(Sender: TObject); 

procedure tbDisconnectedClick(Sender: TObject); 

procedure ClientSocketRead(Sender: TObject; Socket: TCustomWinSocket); 

procedure tbSendClick(Sender: TObject); 

procedure tbCloseClick(Sender: TObject); 

procedure FormShow(Sender: TObject); 

procedure ClientSocketConnect(Sender: TObject; 

Socket: TCustomWinSocket); 

procedure ClientSocketConnecting(Sender: TObject; 

Socket: TCustomWinSocket); 

procedure ClientSocketDisconnect(Sender: TObject; 

Socket: TCustomWinSocket); 

procedure FormClose(Sender: TObject; var Action: TCloseAction); 

procedure ClientSocketError(Sender: TObject; Socket: TCustomWinSocket; 

ErrorEvent: TErrorEvent; var ErrorCode: Integer); 

private 

{ Private declarations } 

public 

{ Public declarations } 

end; 

var 

frmClientMain: TfrmClientMain; 

implementation 

{$R *.DFM} 

//打開套接字連接 

procedure TfrmClientMain.tbConnectedClick(Sender: TObject); 

begin 

ClientSocket.Open ; 

end; 

//關閉套接字連接 

procedure TfrmClientMain.tbDisconnectedClick(Sender: TObject); 

begin 

ClientSocket.Close; 

end; 

//接受服務器端的回複 

procedure TfrmClientMain.ClientSocketRead(Sender: TObject; 

Socket: TCustomWinSocket); 

begin 

Memo1.Lines.Add(Socket.ReceiveText); 

end; 

//發送信息到服務器端 

procedure TfrmClientMain.tbSendClick(Sender: TObject); 

begin 

ClientSocket.Socket.SendText(Edit1.Text); 

end; 

procedure TfrmClientMain.tbCloseClick(Sender: TObject); 

begin 

Close; 

end; 

//設置要連接的服務器端地址 

procedure TfrmClientMain.FormShow(Sender: TObject); 

begin 

ClientSocket.Host := SocketHost; 

end; 

//已經連接到服務器端 

procedure TfrmClientMain.ClientSocketConnect(Sender: TObject; 

Socket: TCustomWinSocket); 

begin 

tbSend.Enabled := True; 

tbDisconnected.Enabled :=True; 

btnSend.Enabled := True; 

StatusBar.Panels[0].Text := '已經連接到 '+ Socket.RemoteHost ; 

end; 

//正在連接到服務器端 

procedure TfrmClientMain.ClientSocketConnecting(Sender: TObject; 

Socket: TCustomWinSocket); 

begin 

StatusBar.Panels[0].Text := '正在連接到服務器... ' ; 

end; 

//當斷開與服務器端的連接時發生 

procedure TfrmClientMain.ClientSocketDisconnect(Sender: TObject; 

Socket: TCustomWinSocket); 

begin 

tbSend.Enabled := False; 

btnSend.Enabled := False; 

tbDisconnected.Enabled := False; 

StatusBar.Panels[0].Text := '已經斷開與 '+ Socket.RemoteHost +' 的連接'; 

end; 

procedure TfrmClientMain.FormClose(Sender: TObject; 

var Action: TCloseAction); 

begin 

ClientSocket.Close ; 

end; 

//當與服務器端的連接發生錯誤時 

procedure TfrmClientMain.ClientSocketError(Sender: TObject; 

Socket: TCustomWinSocket; ErrorEvent: TErrorEvent; 

var ErrorCode: Integer); 

begin 

StatusBar.Panels[0].Text := '與服務器端的連接發生錯誤'; 

ErrorCode := 0; 

end; 

end. 

小結 

上述方法是比較簡單的實現方法，同時也是相對較容易理解的方法。通過這個方法，筆者成功實現了局域網內多個客戶端與服務器端進行Socket通信的功能，同時可以保證一個客戶端的連接、通信或是斷開都不影響其它客戶端的正常通信。 

附錄： 

服務器端窗體和客戶端窗體及組件的屬性設置參加相應的DFM文件。 

uServerMain.pas對應的DFM文件(uServerMain.dfm) 

object frmServerMain: TfrmServerMain 

Left = 297 

Top = 258 

BorderIcons = [biSystemMenu, biMinimize] 

BorderStyle = bsSingle 

Caption = 'ServerSocket' 

ClientHeight = 279 

ClientWidth = 476 

Color = clBtnFace 

Font.Charset = DEFAULT_CHARSET 

Font.Color = clWindowText 

Font.Height = -11 

Font.Name = 'MS Sans Serif' 

Font.Style = [] 

OldCreateOrder = False 

OnClose = FormClose 

OnCreate = FormCreate 

PixelsPerInch = 96 

TextHeight = 13 

object ControlBar1: TControlBar 

Left = 0 

Top = 0 

Width = 476 

Height = 30 

Align = alTop 

AutoSize = True 

TabOrder = 0 

object ToolBar1: TToolBar 

Left = 11 

Top = 2 

Width = 459 

Height = 22 

ButtonHeight = 21 

ButtonWidth = 55 

Caption = 'ToolBar1' 

EdgeInner = esNone 

EdgeOuter = esNone 

Flat = True 

ShowCaptions = True 

TabOrder = 0 

object tbConnect: TToolButton 

Left = 0 

Top = 0 

Caption = ' 連接 ' 

ImageIndex = 0 

OnClick = tbConnectClick 

end 

object tbDisconnected: TToolButton 

Left = 55 

Top = 0 

Caption = '斷開' 

ImageIndex = 4 

OnClick = tbDisconnectedClick 

end 

object tbClose: TToolButton 

Left = 110 

Top = 0 

Caption = '關閉' 

ImageIndex = 3 

OnClick = tbCloseClick 

end 

end 

end 

object Edit1: TEdit 

Left = 0 

Top = 232 

Width = 473 

Height = 21 

TabOrder = 1 

Text = '你好！' 

end 

object Memo1: TMemo 

Left = 0 

Top = 30 

Width = 476 

Height = 195 

Align = alTop 

TabOrder = 2 

end 

object StatusBar: TStatusBar 

Left = 0 

Top = 257 

Width = 476 

Height = 22 

Panels = < 

item 

Width = 50 

end> 

SimplePanel = False 

end 

object ServerSocket: TServerSocket 

Active = False 

Port = 1025 

ServerType = stNonBlocking 

OnListen = ServerSocketListen 

OnGetSocket = ServerSocketGetSocket 

OnClientConnect = ServerSocketClientConnect 

OnClientDisconnect = ServerSocketClientDisconnect 

OnClientRead = ServerSocketClientRead 

OnClientError = ServerSocketClientError 

Left = 368 

end 

end 

uClientMain.pas對應的DFM文件(uClientMain.dfm) 

object frmClientMain: TfrmClientMain 

Left = 361 

Top = 290 

BorderIcons = [biSystemMenu, biMinimize] 

BorderStyle = bsSingle 

Caption = 'ClientSocket' 

ClientHeight = 230 

ClientWidth = 402 

Color = clBtnFace 

Font.Charset = DEFAULT_CHARSET 

Font.Color = clWindowText 

Font.Height = -11 

Font.Name = 'MS Sans Serif' 

Font.Style = [] 

OldCreateOrder = False 

Position = poScreenCenter 

OnClose = FormClose 

OnShow = FormShow 

PixelsPerInch = 96 

TextHeight = 13 

object ControlBar1: TControlBar 

Left = 0 

Top = 0 

Width = 402 

Height = 30 

Align = alTop 

AutoSize = True 

TabOrder = 0 

object ToolBar1: TToolBar 

Left = 11 

Top = 2 

Width = 385 

Height = 22 

ButtonHeight = 21 

ButtonWidth = 55 

Caption = 'ToolBar1' 

EdgeInner = esNone 

EdgeOuter = esNone 

Flat = True 

ShowCaptions = True 

TabOrder = 0 

object tbConnected: TToolButton 

Left = 0 

Top = 0 

Caption = ' 連接 ' 

ImageIndex = 0 

OnClick = tbConnectedClick 

end 

object tbSend: TToolButton 

Left = 55 

Top = 0 

Caption = '發送' 

Enabled = False 

ImageIndex = 1 

OnClick = tbSendClick 

end 

object tbDisconnected: TToolButton 

Left = 110 

Top = 0 

Caption = '斷開' 

Enabled = False 

ImageIndex = 3 

OnClick = tbDisconnectedClick 

end 

object tbClose: TToolButton 

Left = 165 

Top = 0 

Caption = '退出' 

ImageIndex = 2 

OnClick = tbCloseClick 

end 

end 

end 

object Edit1: TEdit 

Left = 0 

Top = 184 

Width = 321 

Height = 21 

TabOrder = 1 

Text = '問候' 

end 

object Memo1: TMemo 

Left = 0 

Top = 30 

Width = 402 

Height = 147 

Align = alTop 

TabOrder = 2 

end 

object StatusBar: TStatusBar 

Left = 0 

Top = 208 

Width = 402 

Height = 22 

Panels = < 

item 

Width = 50 

end> 

SimplePanel = False 

end 

object btnSend: TBitBtn 

Left = 336 

Top = 183 

Width = 60 

Height = 22 

Caption = '發送' 

Enabled = False 

TabOrder = 4 

OnClick = tbSendClick 

end 

object ClientSocket: TClientSocket 

Active = False 

ClientType = ctNonBlocking 

Port = 1025 

OnConnecting = ClientSocketConnecting 

OnConnect = ClientSocketConnect 

OnDisconnect = ClientSocketDisconnect 

OnRead = ClientSocketRead 

OnError = ClientSocketError 

Left = 320 

end 

end