adodatadrivereh.pas

Ehlib.v3.4.for.Delphi5678.rar是DELPHI的三方控件源码.此控件适用于DELPHI5,6,7,8.

{*******************************************************}
{                                                       }
{                     EhLib vX.X                        }
{                                                       }
{         TADODataDriverEh component (not ready)        }
{                                                       }
{      Copyright (c) 2004 by Dmitry V. Bolshakov        }
{                                                       }
{*******************************************************}

unit ADODataDriverEh;

{$I EHLIB.INC}

interface

uses Windows, SysUtils, Classes, Controls, DB,
{$IFDEF EH_LIB_6} Variants, {$ENDIF}
{$IFDEF EH_LIB_5} Contnrs, {$ENDIF}
  ToolCtrlsEh, MemTableDataEh, DataDriverEh, ADODB;

type

  TAssignParameterEhEvent = procedure (Command: TCustomSQLCommandEh;
    MemRecord: TMemoryRecordEh; DataValueVersion: TDataValueVersionEh;
    Parameter: TParameter) of object;

  TADODataDriverEh = class;

  TADODBCommandEh = class(TADOCommand)
  protected
    property ComponentRef;
  end;

{ TADOCommandEh }

  TADOCommandEh = class(TCustomSQLCommandEh)
  private
    FOnAssignParameter: TAssignParameterEhEvent;
    FCommand: TADODBCommandEh;
    function GetParamCheck: Boolean;
    function GetParameters: TParameters;
    function GetDataDriver: TADODataDriverEh;
  protected
    procedure CommandTextChanged(Sender: TObject); override;
    procedure SetParamCheck(const Value: Boolean); virtual;
    procedure SetParameters(const Value: TParameters); virtual;
  public
    constructor Create(ADataDriver: TADODataDriverEh);
    destructor Destroy; override;
    function Execute(var Cursor: TDataSet; var FreeOnEof: Boolean): Integer; override;
    procedure Assign(Source: TPersistent); override;
    procedure DefaultRefreshParameter(MemRecord: TMemoryRecordEh;
      DataValueVersion: TDataValueVersionEh; Parameter: TParameter); virtual;
    procedure RefreshParams(MemRecord: TMemoryRecordEh; DataValueVersion: TDataValueVersionEh); override;

    property DataDriver: TADODataDriverEh read GetDataDriver;
    property OnAssignParameter: TAssignParameterEhEvent read FOnAssignParameter write FOnAssignParameter;
  published
    property CommandText;
    property CommandType;
    property Parameters: TParameters read GetParameters write SetParameters;
    property ParamCheck: Boolean read GetParamCheck write SetParamCheck default True;
  end;

{ TADODataDriverEh }

  TADODataDriverEh = class(TCustomSQLDataDriverEh)
  private
    FSpecParams: TStrings;
    FADOConnection: TADOConnection;
    FOnAssignCommandParameter: TAssignParameterEhEvent;
    FConnectionString: WideString;
    procedure SetSpecParams(const Value: TStrings);
    procedure SetConnection(const Value: TADOConnection);
    procedure SetConnectionString(const Value: WideString);
  protected
    function CreateSelectCommand: TCustomSQLCommandEh; override;
    function CreateUpdateCommand: TCustomSQLCommandEh; override;
    function CreateInsertCommand: TCustomSQLCommandEh; override;
    function CreateDeleteCommand: TCustomSQLCommandEh; override;
    function CreateGetrecCommand: TCustomSQLCommandEh; override;
    procedure AssignCommandParameter(Command: TADOCommandEh;
      MemRecord: TMemoryRecordEh; DataValueVersion: TDataValueVersionEh; Parameter: TParameter); virtual;
    procedure SetAutoIncFields(Fields: TFields; DataStruct: TMTDataStructEh); override;
  public
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
    function CreateDesignCopy: TCustomSQLDataDriverEh; override;
    function CreateDesignDataBase: IInterface; override;
    procedure GetBackUpdatedValues(MemRec: TMemoryRecordEh; Command: TCustomSQLCommandEh; ResDataSet: TDataSet); override;
    procedure DoServerSpecOperations(MemRec: TMemoryRecordEh; Command: TCustomSQLCommandEh; ResDataSet: TDataSet); virtual;

    procedure DefaultAssignCommandParameter(Command: TADOCommandEh;
      MemRecord: TMemoryRecordEh; DataValueVersion: TDataValueVersionEh; Parameter: TParameter); virtual;
  published
    property ADOConnection: TADOConnection read FADOConnection write SetConnection;
    property ConnectionString: WideString read FConnectionString write SetConnectionString;
    property SelectCommand;
    property SelectSQL;
    property UpdateCommand;
    property UpdateSQL;
    property InsertCommand;
    property InsertSQL;
    property DeleteCommand;
    property DeleteSQL;
    property GetrecCommand;
    property GetrecSQL;
    property ProviderDataSet;
    property KeyFields;
    property SpecParams: TStrings read FSpecParams write SetSpecParams;

    property OnExecuteCommand;
    property OnBuildDataStruct;
    property OnGetBackUpdatedValues;
    property OnProduceDataReader;
    property OnAssignFieldValue;
    property OnReadRecord;
    property OnRefreshRecord;
    property OnUpdateRecord;
    property OnAssignCommandParameter: TAssignParameterEhEvent read FOnAssignCommandParameter write FOnAssignCommandParameter;
    property OnUpdateError;
  end;

implementation

{ TADOCommandEh }

constructor TADOCommandEh.Create(ADataDriver: TADODataDriverEh);
begin
  inherited Create(ADataDriver);
  FCommand := TADODBCommandEh.Create(ADataDriver);
  FCommand.ComponentRef := ADataDriver;
end;

destructor TADOCommandEh.Destroy;
begin
  FCommand.Free;
  inherited Destroy;
end;

procedure TADOCommandEh.Assign(Source: TPersistent);
begin
  inherited Assign(Source);
  if Source is TBaseSQLCommandEh then
    with (Source as TBaseSQLCommandEh) do
    begin
      Self.ParamCheck := ParamCheck;
      Self.Parameters := Parameters;
    end;
end;

procedure TADOCommandEh.CommandTextChanged(Sender: TObject);
begin
  inherited CommandTextChanged(Sender);
  FCommand.CommandText := CommandText.Text;
//  if not (csReading in DataDriver.ComponentState) then
//    if ParamCheck then
//      Parameters.ParseSQL(CommandText.Text, True);
end;

procedure TADOCommandEh.RefreshParams(MemRecord: TMemoryRecordEh;
  DataValueVersion: TDataValueVersionEh);
var
  I: Integer;
begin
  for I := 0 to Parameters.Count - 1 do
  begin
    if Assigned(OnAssignParameter)
      then OnAssignParameter(Self, MemRecord, DataValueVersion, Parameters[I])
      else DefaultRefreshParameter(MemRecord, DataValueVersion, Parameters[I]);
  end;
end;

procedure TADOCommandEh.DefaultRefreshParameter(MemRecord: TMemoryRecordEh;
  DataValueVersion: TDataValueVersionEh; Parameter: TParameter);
begin
  DataDriver.AssignCommandParameter(Self, MemRecord, DataValueVersion, Parameter);
end;

function TADOCommandEh.Execute(var Cursor: TDataSet; var FreeOnEof: Boolean): Integer;
var
  ACursor: TDataSet;
begin
  Result := -1;
  Cursor := nil;
  FreeOnEof := False;
  ACursor := nil;
  try
    case CommandType of
      cthSelectQuery, cthUpdateQuery:
        begin
          ACursor := TADOQuery.Create(nil);
          with ACursor as TADOQuery do
          begin
            Connection := DataDriver.ADOConnection;
            ConnectionString := DataDriver.ConnectionString;
            SQL := Self.CommandText;
            Parameters.Assign(Self.Parameters);
            if CommandType = cthSelectQuery then
              Open
            else
            begin
              ExecSQL;
              Result := RowsAffected;
            end;
            Self.Parameters.Assign(Parameters);
          end;
        end;
      cthTable:
        begin
          ACursor := TADOTable.Create(nil);
          with ACursor as TADOTable do
          begin
            Connection := DataDriver.ADOConnection;
            ConnectionString := DataDriver.ConnectionString;
            TableName := Self.CommandText.Text;
            Parameters.Assign(Self.Parameters);
            Open;
            Self.Parameters.Assign(Parameters);
          end;
        end;
      cthStoredProc:
        begin
          ACursor := TADOStoredProc.Create(nil);
          with ACursor as TADOStoredProc do
          begin
            Connection := DataDriver.ADOConnection;
            ConnectionString := DataDriver.ConnectionString;
            ProcedureName := Self.CommandText.Text;
            Parameters.Assign(Self.Parameters);
            ExecProc;
//??            Result := RowsAffected;
            Self.Parameters.Assign(Parameters);
          end;
        end;
    end;
    if ACursor.Active then
    begin
      Cursor := ACursor;
      FreeOnEof := True;
      ACursor := nil;
    end
  finally
    if ACursor <> nil then
      ACursor.Free;
  end;
end;

function TADOCommandEh.GetDataDriver: TADODataDriverEh;
begin
  Result := TADODataDriverEh(inherited DataDriver);
end;

function TADOCommandEh.GetParamCheck: Boolean;
begin
  Result := FCommand.ParamCheck;
end;