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, ConManServer_TLB, StdVcl, DBXpress, FMTBcd, DB, SqlExpr,
  Provider;

type
  TConManDataServer = class(TRemoteDataModule, IConManDataServer)
    conn: TSQLConnection;
    sqlContacts: TSQLDataSet;
    sqlTodos: TSQLDataSet;
    dsContacts: TDataSource;
    pvContacts: TDataSetProvider;
    sqlID: TSQLDataSet;
    sqlContactsCONTACTID: TIntegerField;
    sqlContactsFIRST: TStringField;
    sqlContactsLAST: TStringField;
    sqlContactsDEAR: TStringField;
    sqlContactsTITLE: TStringField;
    sqlContactsCOMPANYNAME: TStringField;
    sqlContactsADDRESS1: TStringField;
    sqlContactsADDRESS2: TStringField;
    sqlContactsCITY: TStringField;
    sqlContactsSTATE: TStringField;
    sqlContactsPOSTALCODE: TStringField;
    sqlContactsCOUNTRY: TStringField;
    sqlContactsPHONE: TStringField;
    sqlContactsFAX: TStringField;
    sqlContactsCELLULAR: TStringField;
    sqlContactsPAGER: TStringField;
    sqlContactsEMAIL: TStringField;
    sqlContactsIMAGE: TBlobField;
    sqlContactsNOTES: TMemoField;
    sqlTodosTODOID: TIntegerField;
    sqlTodosCONTACTID: TIntegerField;
    sqlTodosDESCRIPTION: TStringField;
    sqlTodosSCHEDULED: TSQLTimeStampField;
    sqlTodosCOMPLETED: TSQLTimeStampField;
    procedure RemoteDataModuleCreate(Sender: TObject);
    procedure RemoteDataModuleDestroy(Sender: TObject);
    procedure pvContactsBeforeUpdateRecord(Sender: TObject;
      SourceDS: TDataSet; DeltaDS: TCustomClientDataSet;
      UpdateKind: TUpdateKind; var Applied: Boolean);
  private
    { Private declarations }
    function GetNextID: Integer;
  protected
    class procedure UpdateRegistry(Register: Boolean; const ClassID, ProgID: string); override;
  public
    { Public declarations }
  end;

implementation

uses MainForm;

resourcestring
  SDatabaseIsOpen = 'Cannot perform this operation on an open database';
  
{$R *.DFM}

class procedure TConManDataServer.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 TConManDataServer.RemoteDataModuleCreate(Sender: TObject);
begin
  PostMessage(frmMain.Handle, UM_CONNECT, 1, 0);
end;

procedure TConManDataServer.RemoteDataModuleDestroy(Sender: TObject);
begin
  PostMessage(frmMain.Handle, UM_CONNECT, -1, 0);
end;

procedure TConManDataServer.pvContactsBeforeUpdateRecord(Sender: TObject;
  SourceDS: TDataSet; DeltaDS: TCustomClientDataSet;
  UpdateKind: TUpdateKind; var Applied: Boolean);
begin
  if UpdateKind = ukInsert then
    if SourceDS = sqlContacts then begin
      if DeltaDS.FieldByName('CONTACTID').OldValue <= 0 then
        DeltaDS.FieldByName('CONTACTID').NewValue := GetNextID;
    end else begin
      if DeltaDS.FieldByName('TODOID').OldValue <= 0 then
        DeltaDS.FieldByName('TODOID').NewValue := GetNextID;
    end;
end;

function TConManDataServer.GetNextID: Integer;
begin
  sqlID.ExecSQL;
  Result := sqlID.ParamByName('AValue').AsInteger;
end;

initialization
  TComponentFactory.Create(ComServer, TConManDataServer,
    Class_ConManDataServer, ciMultiInstance, tmApartment);
end.