uaccessdbcontext.~pas

用DELPH写的DAO访问模块.有连接池.应用了各种模块,把数据库操作

/////////////////////////////////////////////////////////////////////////
//                  数据库连接对象 ORACLE 类
//1.数据库连接对象(产品基类 ORACLE 数据库)
//2.通过实现 IConnDataBase，配置数据库连接和命名用数据库Connect对象。
//3.可采用BDE和ADO方式连接后台数据库。
//4.ConnfigDBConnection方法是实际的数据库连接配置
//5.连接配置采用统一方式用TConnDBConfig类实现(委托方式),彻底摆脱数据库
//  配置的受缚.
/////////////////////////////////////////////////////////////////////////

unit uAccessDbContext;

interface

uses
  Classes, ADODB, Controls, DB, DBTables,Windows, SysUtils, Variants,
  uDBContext;

type

  TAccessDbContext = class(TDBContext, IDBContext)
  public
    constructor Create;
    destructor Destroy; override;
  protected
    function getConnection: TCustomConnection; override;
    function Connection: Boolean; override;
  published
    property DBConnection: TCustomConnection read getConnection;
  end;
  
implementation

constructor TAccessDbContext.Create;
begin
  inherited Create;
  pDBConn := TADOConnection.Create(nil);
end;

destructor TAccessDbContext.Destroy;
begin
  pDBConn.Free;
  inherited Destroy;
end;

function  TAccessDbContext.getConnection: TCustomConnection;
begin
  Result := pDBConn;
end;

function TAccessDbContext.Connection: Boolean;
begin

  With DBConfig do
  begin
    ConnStr := 'Provider=Microsoft.Jet.OLEDB.4.0;  Persist Security Info=false; Password="";';
    ConnStr := ConnStr + 'User ID=' + User+';  Data Source='+ DBName;
  end;

  if pDBConn is TADOConnection then
    (pDBConn as TADOConnection).ConnectionString := DBConfig.ConnStr;
  try
    pDBConn.LoginPrompt := false;
    (pDBConn as TADOConnection).Provider := 'Microsoft.Jet.OLEDB.4.0';
    pDBConn.Connected := true;
    Result := true;
  except
    Result := false;
  end;

end;

end.