Delphi Magazine Collection 2001/Delphi Magazine Collection 20001 (2001).iso/DISKS/Issue29/afpelog/AFPELOG.ZIP/afpEventLog.pas

Pascal/Delphi Source File | 1997-10-08 | 6.8 KB | 226 lines

(*******************************************************************************

TafpEventLog Version 1.0
Written by Alfred Petri
Copyright (c) 1997 by Alfred Petri. All rights reserved.

Please send comments to [e-mail]

 ******************************************************************************
 *   Permission to use, copy,  modify, and distribute this software and its   *
 *        documentation without fee for any purpose is hereby granted,        *
 *   provided that the above copyright notice appears on all copies and that  *
 *     both the copyright notice and this permission notice appear in all     *
 *                         supporting documentation.                          *
 *                                                                            *
 * NO REPRESENTATIONS ARE MADE ABOUT THE SUITABILITY OF THIS SOFTWARE FOR ANY *
 *    PURPOSE. IT IS PROVIDED "AS IS" WITHOUT EXPRESS OR IMPLIED WARRANTY.    *
 *        ALFRED PETRI SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY        *
 *                          THE USE OF THIS SOFTWARE.                         *
 ******************************************************************************


This is a non-visual VCL component that encapsulates the NT 4.x REPORTEVENT
function. The purpose of this component is to facilitate the generation of log
entries in the Windows NT Event-Log.

Properties:
- ApplicationName:     Applicationname to appear in Eventlog
- RegisterApplication: If True, a Key of ApplicationName is created in
                                     HKEY_LOCAL_MACHINE
                       \SYSTEM\CurrentControlSet\Services\EventLog\Application
                       If the application is not registered (and thus a
                       corresponding key is not found), EventViewer will
                       not be able to filter messages for this application.
- IncludeUserName:     If True, includes the current user name in the message
                       written to the event log.
- EventType:           Determines the icon to display in Event Viewer.
- EventID:             Integer Positive Number - written to log as is.
- EventCategory:       Integer Positive Number - written to log as is.

Methods:
- LogEvent:           Used to write a message to the Event Log. Typical call:
  afpEventLog1.LogEvent('Password Expired!'#13#10'Contact support!');

  Notes:
*******************************************************************************)

unit afpEventLog;

interface

uses
  Windows, Registry, Messages, SysUtils, Classes, Graphics, Controls, Dialogs;

type
    TEventType = (etError,etWarning,etInformation,etAuditSuccess,etAuditFailure);

  TafpEventLog = class(TComponent)

  private
    { Private declarations }
    FApplicationName: String;
    FRegisterApplication: Boolean;
    FIncludeUserName: Boolean;
    FEventType: TEventType;
    FEventID: DWord;
    FEventCategory: Word;
    FUserName: String;

//    procedure SetupCaption;

  protected
    { Protected declarations }
        procedure SetApplicationName(Value: String);
        procedure SetRegisterApplication(Value: Boolean);
        procedure SetIncludeUserName(Value: Boolean);
        procedure SetEventID(Value: DWord);
        procedure SetEventCategory(Value: Word);

  public
    { Public declarations }
        constructor Create(AOwner: TComponent); override;
        destructor Destroy; override;
        procedure LogEvent(const Line: String);

  published
    { Published declarations }
        property ApplicationName: String
          read FApplicationName write SetApplicationName;
        property RegisterApplication: Boolean
          read FRegisterApplication write SetRegisterApplication;
        property IncludeUserName: Boolean
          read FIncludeUserName write SetIncludeUserName;
        property EventType: TEventType
          read FEventType write FEventType default etInformation;
        property EventID: DWord
          read FEventID write SetEventID;
        property EventCategory: Word
          read FEventCategory write SetEventCategory;
  end;

procedure Register;

{$R afpEventLog.Res}


implementation

procedure Register;
begin
  RegisterComponents('AFP', [TafpEventLog]);
end;


constructor TafpEventLog.Create(AOwner: TComponent);
begin
        inherited Create(AOwner);
        ApplicationName     := '!MyApp';
     EventCategory       := 0;
     EventID             := 0;
     EventType           := etInformation;
     IncludeUserName     := True;
     RegisterApplication := True;
end;

destructor TafpEventLog.Destroy;
begin
    inherited Destroy;
end;

procedure TafpEventLog.SetApplicationName(Value: String);
begin
    if FApplicationName = Value then exit;
    FApplicationName := Value;
end;

procedure TafpEventLog.SetRegisterApplication(Value: Boolean);
begin
    if FRegisterApplication = Value then exit;
    FRegisterApplication := Value;
end;

procedure TafpEventLog.SetIncludeUserName(Value: Boolean);
begin
    if FIncludeUserName = Value then exit;
    FIncludeUserName := Value;
end;

procedure TafpEventLog.SetEventId(Value: DWord);
begin
    if FEventID = Value then exit;
    FEventID := Abs(Value);
end;

procedure TafpEventLog.SetEventCategory(Value: Word);
begin
    if FEventCategory = Value then exit;
    FEventCategory := Abs(Value);
end;

procedure TafpEventLog.LogEvent(const Line: String);
const
    cRegPath = '\SYSTEM\CurrentControlSet\Services\EventLog\Application';
var
    LogHandle:    THandle;
    OK,OK2Run: Boolean;
    eType: Word;
  eMsg, aName: PChar;
    Reg: TRegistry;
  nSize: Dword;
  VersionInfo : TOSVersionInfo;
begin
    VersionInfo.dwOSVersionInfoSize := SizeOf( TOSVersionInfo );
     Ok2Run := False;
    if Windows.GetVersionEx( VersionInfo ) then
        if VersionInfo.dwPlatformId >= VER_PLATFORM_WIN32_NT then
           Ok2Run := True;
  if Ok2Run then
  begin
        if RegisterApplication then
        begin
            Reg := TRegistry.Create;
            try
                with Reg do
                begin
                    RootKey := HKEY_LOCAL_MACHINE;
                  OpenKey( cRegPath + '\' + ApplicationName, True );
                    CloseKey;
                  end;
            finally
                Reg.Free;
            end;
        end;

        LogHandle:= OpenEventLog( NIL, PChar(ApplicationName) );
        if Loghandle<>0 then
        begin
          eType := 0;
              case EventType of
                etError:        eType := 1;
            etWarning:      eType := 2;
                etInformation:  eType := 4;
                etAuditSuccess: eType := 8;
                etAuditFailure: eType := 16;
            end;

        FUsername := #13#10;
            If IncludeUserName then
            begin
              nSize := 20 ; // Max UserName
              aName := stralloc ( nSize+1 );
              OK := GetUserName( aName, nSize );
               if not OK then strcopy( aName, 'N/A' );
              FUserName := FUserName + 'User: ' + aName + #13#10;
              strDispose( aName );
            end;
            eMsg := Pchar(FUserName + Line);

            ReportEvent(LogHandle, eType, EventCategory, EventID, NIL, 1, 0, @eMsg, NIL);
             CloseEventLog(LogHandle);
        end;
    end;
end;

end.