Application应用框架思考(二) 之[数据访问层]

Application应用框架思考(二) 之[数据访问层] public interface IDataAccessLayer { void BeginTransaction(); void Close(); void CommitTransaction(); string ConnectionString { get; set; } void Dispose(); void Execute(); System.Data.IDataReader ExecuteDataReader(string commandText, System.Data.IDataParameter[] commandParameters); System.Data.IDataReader ExecuteDataReader(string commandText, System.Data.CommandType commandType); System.Data.IDataReader ExecuteDataReader(string commandText, System.Data.CommandType commandType, System.Data.IDataParameter[] commandParameters); System.Data.IDataReader ExecuteDataReader(string commandText); System.Data.DataSet ExecuteDataSet(string commandText, System.Data.CommandType commandType, System.Data.IDataParameter[] commandParameters); System.Data.DataSet ExecuteDataSet(string commandText, System.Data.CommandType commandType); System.Data.DataSet ExecuteDataSet(string commandText); System.Data.DataSet ExecuteDataSet(string commandText, System.Data.IDataParameter[] commandParameters); System.Data.DataTable ExecuteDataTable(string pSQL); System.Data.DataSet ExecuteKDDataSet(string pSQL); int ExecuteQuery(string commandText, System.Data.CommandType commandType, System.Data.IDataParameter[] commandParameters); int ExecuteQuery(string commandText, System.Data.IDataParameter[] commandParameters); int ExecuteQuery(string commandText); int ExecuteQuery(string commandText, System.Data.CommandType commandType); object ExecuteScalar(string commandText, System.Data.CommandType commandType, System.Data.IDataParameter[] commandParameters); object ExecuteScalar(string commandText, System.Data.CommandType commandType); object ExecuteScalar(string commandText); object ExecuteScalar(string commandText, System.Data.IDataParameter[] commandParameters); int ExecuteSp(string commandText, System.Data.CommandType commandType); int ExecuteSp(string commandText, System.Data.CommandType commandType, System.Data.IDataParameter[] commandParameters); int ExecuteSp(string commandText); System.Data.IDbCommand GeDataProviderCommand(); DataProviderType GetCurrentDataProviderType(); System.Data.IDbConnection GetDataProviderConnection(); System.Data.IDbDataAdapter GetDataProviderDataAdapter(); System.Data.Common.DbCommand GetDbCommand(); System.Data.Common.DbCommandBuilder GetDbCommandBuilder(); System.Data.Common.DbConnection GetDbConnection(); System.Data.Common.DbDataAdapter GetDbDataAdapter(); string getFieldValue(string FieldName); bool IsExistsField(string FieldName, string TableName); bool IsExistsTable(string TableName, string UserName); bool Open(); void ReOpen(string connectionString); void RollbackTransaction(); string SQL { get; set; } System.Data.ConnectionState State { get; } } /// <summary> /// Defines the DataAccessLayer implemented data provider types. /// </summary> public enum DataProviderType { Access, Odbc, OleDb, Oracle, Sql } //抽象类 public abstract class DataAccessLayerBaseClass : IDataAccessLayer { //相关接口实现 } public class OracleDataAccessLayer : DataAccessLayerBaseClass { //Oracle相关实现 } public class SqlDataAccessLayer: DataAccessLayerBaseClass { //SQLServer相关实现 } public class OleDbDataAccessLayer: DataAccessLayerBaseClass { //OleDb相关实现 } public class OdbcDataAccessLayerDataAccessLayerBaseClass { //Odbc相关实现 } public sealed class DataAccessLayerFactory { private DataAccessLayerFactory() { } public static DataAccessLayerBaseClass GetDataAccessLayer() { //... } public static DataAccessLayerBaseClass GetDataAccessLayer(DataProviderType dataProviderType, string connectionString) { // construct specific data access provider class switch (dataProviderType) { case DataProviderType.Access: case DataProviderType.OleDb: return new OleDbDataAccessLayer(connectionString); case DataProviderType.Odbc: return new OdbcDataAccessLayer(connectionString); case DataProviderType.Oracle: return new OracleDataAccessLayer(connectionString); case DataProviderType.Sql: return new SqlDataAccessLayer(connectionString); default: throw new ArgumentException("Invalid data access layer provider type."); } } }