remotedatamodule.pas

Delphi Kylix Database Development 附书代码

unit RemoteDataModule;

{$WARN SYMBOL_PLATFORM OFF}

interface

uses
  Windows, Messages, SysUtils, Classes, ComServ, ComObj, VCLCom, DataBkr,
  DBClient, StatelessServer_TLB, StdVcl, DBXpress, FMTBcd, DB, SqlExpr,
  Provider, Variants;

type
  TStatelessServerData = class(TRemoteDataModule, IStatelessServerData)
    conn: TSQLConnection;
    sqlContacts: TSQLDataSet;
    pvContacts: TDataSetProvider;
    procedure pvContactsGetData(Sender: TObject;
      DataSet: TCustomClientDataSet);
    procedure pvContactsAfterGetRecords(Sender: TObject;
      var OwnerData: OleVariant);
    procedure pvContactsBeforeGetRecords(Sender: TObject;
      var OwnerData: OleVariant);
  private
    { Private declarations }
  protected
    class procedure UpdateRegistry(Register: Boolean; const ClassID, ProgID: string); override;
  public
    { Public declarations }
  end;

implementation

{$R *.DFM}

class procedure TStatelessServerData.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 TStatelessServerData.pvContactsGetData(Sender: TObject;
  DataSet: TCustomClientDataSet);
begin
  DataSet.Last;
  pvContacts.Tag := DataSet.FieldByName('ID').AsInteger;
end;

procedure TStatelessServerData.pvContactsAfterGetRecords(Sender: TObject;
  var OwnerData: OleVariant);
begin
  OwnerData := pvContacts.Tag;
end;

procedure TStatelessServerData.pvContactsBeforeGetRecords(Sender: TObject;
  var OwnerData: OleVariant);
begin
  if not VarIsEmpty(OwnerData) then begin
    sqlContacts.Params.ParamValues['MinID'] := OwnerData;
    sqlContacts.Refresh;
  end else begin
    sqlContacts.Params.ParamValues['MinID'] := 0;
//    sqlContacts.Open;
  end;
end;

initialization
  TComponentFactory.Create(ComServer, TStatelessServerData,
    Class_StatelessServerData, ciMultiInstance, tmApartment);
end.