unit2.pas

三层数据库应用程序的例子,包括应用服务器和前台程序.

unit Unit2;

{$WARN SYMBOL_PLATFORM OFF}

interface

uses
  Windows, Messages, SysUtils, Classes, ComServ, ComObj, VCLCom, DataBkr,
  DBClient, Project1_TLB, StdVcl, Provider, ADODB, DB;

type
  TTestServer = class(TRemoteDataModule, ITestServer)
    ADOConnection1: TADOConnection;
    ADOTable1: TADOTable;
    ADOQuery1: TADOQuery;
    ADOStoredProc1: TADOStoredProc;
    DataSetProvider1: TDataSetProvider;
    DataSetProvider2: TDataSetProvider;
    DataSetProvider3: TDataSetProvider;
    procedure RemoteDataModuleCreate(Sender: TObject);
    procedure RemoteDataModuleDestroy(Sender: TObject);
    procedure ADOQuery1AfterOpen(DataSet: TDataSet);
  private
    { Private declarations }
  protected
    class procedure UpdateRegistry(Register: Boolean; const ClassID, ProgID: string); override;
  public
    { Public declarations }
  end;

implementation

uses Unit1;

{$R *.DFM}

class procedure TTestServer.UpdateRegistry(Register: Boolean; const ClassID, ProgID: string);
begin
  if Register then
  begin
    inherited UpdateRegistry(Register, ClassID, ProgID);
    EnableSocketTransport(ClassID);
    EnableWebTransport(ClassID);
  end else
  begin
    DisableSocketTransport(ClassID);
    DisableWebTransport(ClassID);
    inherited UpdateRegistry(Register, ClassID, ProgID);
  end;
end;

procedure TTestServer.RemoteDataModuleCreate(Sender: TObject);
begin
  //增加一位前台的在线者(调用Form1上的过程)
  Form1.UpdateClientCount(1);
end;

procedure TTestServer.RemoteDataModuleDestroy(Sender: TObject);
begin
  Form1.UpdateClientCount(-1);
end;

procedure TTestServer.ADOQuery1AfterOpen(DataSet: TDataSet);
begin
  Form1.incQueryCount;
end;

initialization
  TComponentFactory.Create(ComServer, TTestServer,
    Class_TestServer, ciMultiInstance, tmApartment);
end.