IData.cs

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.Common;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Com.Ddlev.Data
{
    /// <summary>
    /// 数据库接口(对继承该接口的类使用单件模式)
    /// </summary>
    public interface IData : IDisposable
    {
        /// <summary>
        /// 连接的字符串
        /// </summary>
        string ConnectionString
        {
            get;
        }
        /// <summary>
        /// 数据库连接
        /// </summary>
        DbConnection Conn
        {
            get;
        }
        /// <summary>
        /// 打开数据库连接
        /// </summary>
        /// <returns></returns>
        void OpenData();
        /// <summary>
        /// 关闭数据库连接
        /// </summary>
        /// <returns></returns>
        void CloseData();
        /// <summary>
        /// 执行SQL或者存储过程并返回受影响的行数（用事务的方式）
        /// </summary>
        /// <param name="cmdType">sql文本还是存储过程</param>
        /// <param name="cmdText">sql语句或者存储过程的名称(如果是存储过程，存储过程里面必须包含事务)</param>
        /// <param name="ldt">参数集合</param>
        /// <returns></returns>
        int ExecuteNonQuery( string cmdText,  List<DataItemType> ldt=null, CommandType cmdType = CommandType.Text);
        /// <summary>
        /// 分开执行多条sql,如果有一条错误，全部回滚，如果是存储过程，则存储过程里面不能含有事务
        /// </summary>
        /// <param name="cmdType">sql文本还是存储过程</param>
        /// <param name="cmdTexts">sql语句或者存储过程的名称</param>
        /// <param name="ldt">参数集合</param>
        /// <returns></returns>
        int ExecuteNonQuery(string[] cmdTexts, List<DataItemType> ldt = null, CommandType cmdType = CommandType.Text);



        /// <summary>
        /// 获取一个IDataReader
        /// </summary>
        /// <param name="cmdType">sql文本还是存储过程</param>
        /// <param name="cmdText">sql语句或者存储过程的名称</param>
        /// <param name="ldt">参数集合</param>
        /// <returns>IDataReader要手动关闭</returns>
        IDataReader ExecuteIReader(string cmdText, List<DataItemType> ldt=null, CommandType cmdType = CommandType.Text);

        /// <summary>
        /// 返回首行首列的值（object）
        /// </summary>
        /// <param name="cmdType">sql文本还是存储过程</param>
        /// <param name="cmdText">sql语句或者存储过程的名称</param>
        /// <param name="ldt">参数集合</param>
        /// <returns></returns>
        object ExecuteScalar( string cmdText, List<DataItemType> ldt=null, CommandType cmdType = CommandType.Text);
        /// <summary>
        /// 执行查询并返回数据集(DataTable)
        /// </summary>
        /// <param name="cmdType">sql文本还是存储过程</param>
        /// <param name="cmdText">sql语句或者存储过程的名称</param>
        /// <param name="ldt">参数集合</param>
        /// <returns></returns>
        DataTable ExecQuery( string cmdText, List<DataItemType> ldt=null, CommandType cmdType = CommandType.Text);
        /// <summary>
        /// 备份数据库
        /// </summary>
        /// <param name="dbname">数据库名称</param>
        /// <param name="filename">备份的路径和名称</param>
        bool BackUp(string dbname, string filename);
        /// <summary>
        /// 恢复数据库
        /// </summary>
        /// <param name="dbname">数据库名称</param>
        /// <param name="filename">要恢复的备份数据库的路径和名称</param>
        bool Recoverd(string dbname, string filename);

        /// <summary>
        /// 设置成员
        /// </summary>
        /// <param name="ldt"></param>
        /// <returns></returns>
        DbParameter[] SetDbParameter(List<DataItemType> ldt);

        /// <summary>
        /// 设置成员
        /// </summary>
        /// <param name="ldt"></param>
        /// <returns></returns>
        IDataParameter[] SetDbParameter(IList<DataItemType> ldt);
    }


}