一个基础数据访问库

在新的公司一切都非常原始,不知能不能改变.坚持一下看下不能改变实际不行再选其他路:
似乎公司现有员工对持久层不能愿意,为了方便自己开发只好写一个helper(公司用.net1.1,我的框架也无用武之地).虽然是个ado的helper但出发点还把command抽象一次来实现DAL的数据库无关性.
代码直接贴出来了,有需要朋友可以得到一个思路.

public abstract class ConnBase:IDisposable    
    {
        public ConnBase(string connectionstring)
        {
            mConnection = CreateConnection(connectionstring); 
            mConnection.Open();
        }

        abstract#region abstract
        protected abstract IDbConnection CreateConnection(string connectionstring);
        public abstract  IDbCommand CreateCommand(string sql);
        public abstract IDbDataAdapter CreateAdapter();
        public abstract IDataParameter CreateParameter();
        protected abstract string NamePrefix
        {
            get;
        }
    
        #endregion

        public IDataParameter CreateParameter(string name,object value)
        {
            IDataParameter dp = CreateParameter();
            dp.ParameterName = NamePrefix+ name;
            dp.Value = value;
            return dp;
        }
        public IDataParameter CreateParameter(string name,object value,ParameterDirection pd)
        {
            IDataParameter dp = CreateParameter(name,value);
            dp.Direction = pd;
            return dp;
        }
        public IDbCommand CreateCommand(String sql,CommandType ct, params IDataParameter[] paramters)
        {
            IDbCommand cmd = CreateCommand(sql,paramters);
            cmd.CommandType = ct;
            return cmd;
        }
        public  IDbCommand CreateCommand(string sql,params IDataParameter[] paramters)
        {
            IDbCommand cmd = CreateCommand(sql);
            if(paramters != null)
            {
                foreach(IDataParameter dp in paramters)
                {
                    cmd.Parameters.Add(dp);
                }
            }
            return cmd;
            

        }
                                  
        private IDbConnection mConnection;
        protected IDbConnection Connection
        {
            get
            {
                return mConnection;
            }
        
        }
        private IDbTransaction mTransaction;
        protected IDbTransaction Transaction
        {
            get
            {
                return mTransaction;
            }

        }
        public void BeginTran()
        {
            mTransaction = Connection.BeginTransaction();
        }
        public void Commit()
        {
            mTransaction.Commit();
            mTransaction = null;
        }
        
        public int ExecuteNonQuery(Command cmd)
        {
            return cmd.CreateCommand(this).ExecuteNonQuery();
        }
        public  IDataReader ExecuteReader(Command cmd)
        {
            return cmd.CreateCommand(this).ExecuteReader();
        }
        
        public  object ExecuteScalar(Command cmd)
        {
            return cmd.CreateCommand(this).ExecuteScalar();
            
        }
    
        public DataSet ExecuteDataSet(Command cmd)
        {
            IDbDataAdapter adapter = CreateAdapter();
            adapter.SelectCommand = cmd.CreateCommand(this);
            DataSet ds = new DataSet();
            adapter.Fill(ds);
            return ds;
        }
        public IDataParameter[] CopyToParameter(IList parameters)
        {
            Array ap =  Array.CreateInstance(typeof(IDataParameter),parameters.Count);
            parameters.CopyTo(ap,0);
            return (IDataParameter[])ap;
        }

        IDisposable 成员#region IDisposable 成员
        public void Dispose()
        {
            // TODO:  添加 ConnBase.Dispose 实现
            try
            {
                if(Transaction != null)
                    Transaction.Rollback();
            }
            finally
            {
                Connection.Close();
            }
        }

        #endregion
    }

public class Command
    {
        public Command(string text)
        {
            Text = text;
        }
        private string mText;
        public string Text
        {
            get
            {
                return mText;
            }
            set
            {
                mText = value;
            }
        }
        private CommandType mCommandType;
        public CommandType CommandType
        {
            get
            {
                return mCommandType;
            }
            set
            {
                mCommandType = value;
            }
            
        }
        private ArrayList mParameters = new ArrayList();
        public ArrayList Parameters
        {
            get
            {
                return mParameters;
            }
        }

        public void AddParameter(string name,string value)
        {
            AddParameter(name,value,ParameterDirection.Input);
        }
        public void AddParameter(string name,string value,ParameterDirection pd)
        {
            Parameter p = new Parameter();
            p.Name = name;
            p.Value = value;
            p.Direction = pd;
            Parameters.Add(p);
        }
        public class Parameter
        {
            private string mName;
            public string Name
            {
                get
                {
                    return mName;
                }
                set
                {
                    mName = value;
                }
            }
            private object mValue;
            public object Value
            {
                get
                {
                    return mValue;
                }
                set
                {
                    mValue = value;
                }
            }
            private ParameterDirection mDirection = ParameterDirection.Input;
            public ParameterDirection Direction
            {
                get
                {
                    return mDirection;
                }
                set
                {
                    mDirection = value;
                }
            }
        }
        public IDbCommand CreateCommand(ConnBase conn)
        {
            IDbCommand cmd = conn.CreateCommand(Text);
            cmd.CommandType = CommandType;
            foreach(Parameter p in Parameters)
            {
                cmd.Parameters.Add(conn.CreateParameter(p.Name,p.Value,p.Direction));
            }
            return cmd;
        }
    }

    public class OracleConn:ConnBase
    {
        public OracleConn(string connstring):base(connstring){}
        public override IDbDataAdapter CreateAdapter()
        {
            return new OracleDataAdapter();
        }
        public override IDbCommand CreateCommand(string sql)
        {
            IDbCommand cmd= new OracleCommand(sql);
            cmd.Connection = Connection;
            if(Transaction != null)
                cmd.Transaction = Transaction;
            return cmd;
            
        }
        protected override IDbConnection CreateConnection(string connectionstring)
        {
            return new OracleConnection(connectionstring);

        }
        
        public override IDataParameter CreateParameter()
        {
            return new OracleParameter();
        }

        protected override string NamePrefix
        {
            get
            {
                return ":";
            }
        }




    }
    public class MSSql:ConnBase
    {
        public MSSql(string connstring):base(connstring){}
        public override IDbDataAdapter CreateAdapter()
        {
            return new SqlDataAdapter() ;
        }
        public override IDbCommand CreateCommand(string sql)
        {
            IDbCommand cmd= new SqlCommand(sql);
            cmd.Connection = Connection;
            if(Transaction != null)
                cmd.Transaction = Transaction;
            return cmd;
        }
        protected override IDbConnection CreateConnection(string connectionstring)
        {
            return new SqlConnection(connectionstring);
        }
        public override IDataParameter CreateParameter()
        {
            return new SqlParameter();
        }
        protected override string NamePrefix
        {
            get
            {
                return "@";
            }
        }





    }

    public class Access:ConnBase
    {
        public Access(string connstring):base(connstring){}
        public override IDbDataAdapter CreateAdapter()
        {
            return new OleDbDataAdapter();
        }
        public override IDbCommand CreateCommand(string sql)
        {
            IDbCommand cmd = new OleDbCommand(sql);
            cmd.Connection = Connection;
            if(Transaction != null)
                cmd.Transaction = Transaction;
            return cmd;
        }
        protected override IDbConnection CreateConnection(string connectionstring)
        {
            return new OleDbConnection(connectionstring);
                                          
        }
        public override IDataParameter CreateParameter()
        {
            return new OleDbParameter();
        }
        protected override string NamePrefix
        {
            get
            {
                return "@";
            }
        }




    }