tncli1.pas

< Delphi网络通信协议分析与应用实现>>一书的源代码。

unit TnCli1;

interface

uses
  WinTypes, WinProcs, Messages, SysUtils, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, IniFiles, EmulVT, TnEmulVT, WSocket, Winsock;

type
  TTelnetForm = class(TForm)
    TnEmulVT1: TTnEmulVT;
    ConnectButton: TButton;
    Label1: TLabel;
    HostNameEdit: TEdit;
    Label2: TLabel;
    PortEdit: TEdit;
    DisconnectButton: TButton;
    StatusLabel: TLabel;
    SendButton: TButton;
    OptionsButton: TButton;
    LocalEchoCheckBox: TCheckBox;
    RequestLocalEchoOnButton: TButton;
    RequestLocalEchoOffButton: TButton;
    procedure ConnectButtonClick(Sender: TObject);
    procedure FormResize(Sender: TObject);
    procedure DisconnectButtonClick(Sender: TObject);
    procedure TnEmulVT1SessionConnected(Sender: TObject);
    procedure TnEmulVT1SessionClosed(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure SendButtonClick(Sender: TObject);
    procedure OptionsButtonClick(Sender: TObject);
    procedure FormShow(Sender: TObject);
    procedure LocalEchoCheckBoxClick(Sender: TObject);
    procedure TnEmulVT1LocalEcho(Sender: TObject);
    procedure RequestLocalEchoOnButtonClick(Sender: TObject);
    procedure RequestLocalEchoOffButtonClick(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
  private
    FIniFileName : String;
    FInitialized : Boolean;
  public
    { D閏larations publiques }
  end;

var
  TelnetForm: TTelnetForm;

implementation

{$R *.DFM}
const
    SectionWindow = 'Window';
    KeyTop        = 'Top';
    KeyLeft       = 'Left';
    KeyWidth      = 'Width';
    KeyHeight     = 'Height';
    SectionData   = 'Data';
    KeyHostName   = 'HostName';
    KeyPort       = 'Port';

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procedure TTelnetForm.FormCreate(Sender: TObject);
begin
    FIniFileName := LowerCase(ExtractFileName(Application.ExeName));
    FIniFileName := Copy(FIniFileName, 1, Length(FIniFileName) - 3) + 'ini';
    StatusLabel.Caption := 'Not connected';
    TnEmulVT1.RestoreOptions;

end;


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procedure TTelnetForm.FormShow(Sender: TObject);
var
    WinsockData : TWSADATA;
    IniFile     : TIniFile;
begin
    if not FInitialized then begin
        FInitialized := TRUE;
        IniFile := TIniFile.Create(FIniFileName);
        HostNameEdit.Text  := IniFile.ReadString(SectionData, KeyHostName,
                                                 'localhost');
        PortEdit.Text      := IniFile.ReadString(SectionData, KeyPort,
                                                 'telnet');

        Width  := IniFile.ReadInteger(SectionWindow, KeyWidth,  Width);
        Height := IniFile.ReadInteger(SectionWindow, KeyHeight, Height);
        Top    := IniFile.ReadInteger(SectionWindow, KeyTop,    (Screen.Height - Height) div 2);
        Left   := IniFile.ReadInteger(SectionWindow, KeyLeft,   (Screen.Width - Width) div 2);

        IniFile.Free;
        TnEmulVT1.Clear;
        WinsockData := WinsockInfo;
        StatusLabel.Caption := StrPas(WinsockData.szDescription);
    end;
end;


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procedure TTelnetForm.FormClose(Sender: TObject; var Action: TCloseAction);
var
    IniFile : TIniFile;
begin
    IniFile := TIniFile.Create(FIniFileName);
    IniFile.WriteString(SectionData, KeyHostName,  HostNameEdit.Text);
    IniFile.WriteString(SectionData, KeyPort,      PortEdit.Text);
    IniFile.WriteInteger(SectionWindow, KeyTop,    Top);
    IniFile.WriteInteger(SectionWindow, KeyLeft,   Left);
    IniFile.WriteInteger(SectionWindow, KeyWidth,  Width);
    IniFile.WriteInteger(SectionWindow, KeyHeight, Height);
    IniFile.Free;
end;


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procedure TTelnetForm.ConnectButtonClick(Sender: TObject);
begin
    StatusLabel.Caption := 'Connecting';
    Refresh;
    ConnectButton.Enabled := FALSE;
    try
        TnEmulVT1.Disconnect;
        TnEmulVT1.Port     := PortEdit.Text;
        TnEmulVT1.HostName := HostNameEdit.Text;
        TnEmulVT1.RestoreOptions;
        { This can take quite a long time when hostname is unknown and }
        { if DNS feature is enabled (2 or 3 minutes !)                 }
        TnEmulVT1.Connect;
    except
        ConnectButton.Enabled := TRUE;
        raise;
    end;
end;


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procedure TTelnetForm.DisconnectButtonClick(Sender: TObject);
begin
    TnEmulVT1.Disconnect;
end;


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procedure TTelnetForm.TnEmulVT1SessionConnected(Sender: TObject);
begin
    DisconnectButton.Enabled := TRUE;
    StatusLabel.Caption      := 'Connected';
end;


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procedure TTelnetForm.TnEmulVT1SessionClosed(Sender: TObject);
begin
    DisconnectButton.Enabled := FALSE;
    ConnectButton.Enabled    := TRUE;
    StatusLabel.Caption      := 'Not connected';
end;


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procedure TTelnetForm.FormResize(Sender: TObject);
begin
    TnEmulVT1.Width  := ClientWidth;
    TnEmulVT1.Height := ClientHeight - TnEmulVT1.Top;
end;


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procedure TTelnetForm.SendButtonClick(Sender: TObject);
begin
    TnEmulVT1.SendStr('Hello world !' + #13#10);
    ActiveControl := TnEmulVT1;
end;


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procedure TTelnetForm.OptionsButtonClick(Sender: TObject);
begin
    TnEmulVT1.HostName := HostNameEdit.Text;
    TnEmulVT1.EditOptions;
end;


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procedure TTelnetForm.TnEmulVT1LocalEcho(Sender: TObject);
begin
    if TnEmulVT1.GetLocalEcho then
        StatusLabel.Caption := 'Remote will not echo'
    else
        StatusLabel.Caption := 'Remote will echo';
end;


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procedure TTelnetForm.LocalEchoCheckBoxClick(Sender: TObject);
begin
    TnEmulVT1.LocalEcho := LocalEchoCheckBox.Checked;
    ActiveControl       := TnEmulVT1;
end;


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procedure TTelnetForm.RequestLocalEchoOnButtonClick(Sender: TObject);
begin
    TnEmulVT1.RequestLocalEcho(TRUE);
    ActiveControl       := TnEmulVT1;
end;


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procedure TTelnetForm.RequestLocalEchoOffButtonClick(Sender: TObject);
begin
    TnEmulVT1.RequestLocalEcho(FALSE);
    ActiveControl       := TnEmulVT1;
end;


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end.