/// <summary>

/// 类说明：公共的数据库访问访问类

/// 编码日期：2010-4-22

/// 编 码 人：苏飞

/// 联系方式：361983679  Email：[url=mailto:sufei.1013@163.com]sufei.1013@163.com[/url]  Blogs:[url=http://www.sufeinet.com]http://www.sufeinet.com[/url]

/// 修改日期：2013-08-15

/// </summary>

using System;

using System.Collections.Generic;

using System.Text;

using System.Data;

using System.Data.SqlClient;

using System.Collections;

namespace DotNet.Utilities

{

    /// <summary>

    /// 数据库的通用访问代码 苏飞修改

    /// 此类为抽象类，

    /// 不允许实例化，在应用时直接调用即可

    /// </summary>

    public abstract class SqlHelper

    {

        /// <summary>

        /// 数据库连接字符串

        /// </summary>

        public static readonly string connectionString = System.Configuration.ConfigurationSettings.AppSettings["con"].ToString().Trim();

        // Hashtable to store cached parameters

        private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable());

        #region //ExecteNonQuery方法

        /// <summary>

        ///执行一个不需要返回值的SqlCommand命令，通过指定专用的连接字符串。

        /// 使用参数数组形式提供参数列表

        /// </summary>

        /// <param name="connectionString">一个有效的数据库连接字符串</param>

        /// <param name="cmdType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param>

        /// <param name="cmdText">存储过程的名字或者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>返回一个数值表示此SqlCommand命令执行后影响的行数</returns>

        public static int ExecteNonQuery(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            SqlCommand cmd = new SqlCommand();

            using (SqlConnection conn = new SqlConnection(connectionString))

            {

                //通过PrePareCommand方法将参数逐个加入到SqlCommand的参数集合中

                PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);

                int val = cmd.ExecuteNonQuery();

                //清空SqlCommand中的参数列表

                cmd.Parameters.Clear();

                return val;

            }

        }

        /// <summary>

        ///执行一个不需要返回值的SqlCommand命令，通过指定专用的连接字符串。

        /// 使用参数数组形式提供参数列表

        /// </summary>

        /// <param name="cmdType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param>

        /// <param name="cmdText">存储过程的名字或者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>返回一个数值表示此SqlCommand命令执行后影响的行数</returns>

        public static int ExecteNonQuery(CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            return ExecteNonQuery(connectionString, cmdType, cmdText, commandParameters);

        }

        /// <summary>

        ///存储过程专用

        /// </summary>

        /// <param name="cmdText">存储过程的名字</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>返回一个数值表示此SqlCommand命令执行后影响的行数</returns>

        public static int ExecteNonQueryProducts(string cmdText, params SqlParameter[] commandParameters)

        {

            return ExecteNonQuery(CommandType.StoredProcedure, cmdText, commandParameters);

        }

        /// <summary>

        ///Sql语句专用

        /// </summary>

        /// <param name="cmdText">T_Sql语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>返回一个数值表示此SqlCommand命令执行后影响的行数</returns>

        public static int ExecteNonQueryText(string cmdText, params SqlParameter[] commandParameters)

        {

            return ExecteNonQuery(CommandType.Text, cmdText, commandParameters);

        }

        #endregion

        #region//GetTable方法

        /// <summary>

        /// 执行一条返回结果集的SqlCommand，通过一个已经存在的数据库连接

        /// 使用参数数组提供参数

        /// </summary>

        /// <param name="connecttionString">一个现有的数据库连接</param>

        /// <param name="cmdTye">SqlCommand命令类型</param>

        /// <param name="cmdText">存储过程的名字或者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>返回一个表集合(DataTableCollection)表示查询得到的数据集</returns>

        public static DataTableCollection GetTable(string connecttionString, CommandType cmdTye, string cmdText, SqlParameter[] commandParameters)

        {

            SqlCommand cmd = new SqlCommand();

            DataSet ds = new DataSet();

            using (SqlConnection conn = new SqlConnection(connecttionString))

            {

                PrepareCommand(cmd, conn, null, cmdTye, cmdText, commandParameters);

                SqlDataAdapter adapter = new SqlDataAdapter();

                adapter.SelectCommand = cmd;

                adapter.Fill(ds);

            }

            DataTableCollection table = ds.Tables;

            return table;

        }

        /// <summary>

        /// 执行一条返回结果集的SqlCommand，通过一个已经存在的数据库连接

        /// 使用参数数组提供参数

        /// </summary>

        /// <param name="cmdTye">SqlCommand命令类型</param>

        /// <param name="cmdText">存储过程的名字或者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>返回一个表集合(DataTableCollection)表示查询得到的数据集</returns>

        public static DataTableCollection GetTable(CommandType cmdTye, string cmdText, SqlParameter[] commandParameters)

        {

            return GetTable(SqlHelper.connectionString, cmdTye, cmdText, commandParameters);

        }

        /// <summary>

        /// 存储过程专用

        /// </summary>

        /// <param name="cmdText">存储过程的名字或者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>返回一个表集合(DataTableCollection)表示查询得到的数据集</returns>

        public static DataTableCollection GetTableProducts(string cmdText, SqlParameter[] commandParameters)

        {

            return GetTable(CommandType.StoredProcedure, cmdText, commandParameters);

        }

        /// <summary>

        /// Sql语句专用

        /// </summary>

        /// <param name="cmdText"> T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>返回一个表集合(DataTableCollection)表示查询得到的数据集</returns>

        public static DataTableCollection GetTableText(string cmdText, SqlParameter[] commandParameters)

        {

            return GetTable(CommandType.Text, cmdText, commandParameters);

        }

        #endregion

        /// <summary>

        /// 为执行命令准备参数

        /// </summary>

        /// <param name="cmd">SqlCommand 命令</param>

        /// <param name="conn">已经存在的数据库连接</param>

        /// <param name="trans">数据库事物处理</param>

        /// <param name="cmdType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param>

        /// <param name="cmdText">Command text，T-SQL语句 例如 Select * from Products</param>

        /// <param name="cmdParms">返回带参数的命令</param>

        private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, CommandType cmdType, string cmdText, SqlParameter[] cmdParms)

        {

            //判断数据库连接状态

            if (conn.State != ConnectionState.Open)

                conn.Open();

            cmd.Connection = conn;

            cmd.CommandText = cmdText;

            //判断是否需要事物处理

            if (trans != null)

                cmd.Transaction = trans;

            cmd.CommandType = cmdType;

            if (cmdParms != null)

            {

                foreach (SqlParameter parm in cmdParms)

                    cmd.Parameters.Add(parm);

            }

        }

        /// <summary>

        /// Execute a SqlCommand that returns a resultset against the database specified in the connection string

        /// using the provided parameters.

        /// </summary>

        /// <param name="connectionString">一个有效的数据库连接字符串</param>

        /// <param name="cmdType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param>

        /// <param name="cmdText">存储过程的名字或者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>A SqlDataReader containing the results</returns>

        public static SqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            SqlCommand cmd = new SqlCommand();

            SqlConnection conn = new SqlConnection(connectionString);

            // we use a try/catch here because if the method throws an exception we want to

            // close the connection throw code, because no datareader will exist, hence the

            // commandBehaviour.CloseConnection will not work

            try

            {

                PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);

                SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);

                cmd.Parameters.Clear();

                return rdr;

            }

            catch

            {

                conn.Close();

                throw;

            }

        }

        #region//ExecuteDataSet方法

        /// <summary>

        /// return a dataset

        /// </summary>

        /// <param name="connectionString">一个有效的数据库连接字符串</param>

        /// <param name="cmdType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param>

        /// <param name="cmdText">存储过程的名字或者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>return a dataset</returns>

        public static DataSet ExecuteDataSet(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            SqlCommand cmd = new SqlCommand();

            try

            {

                using (SqlConnection conn = new SqlConnection(connectionString))

                {

                    PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);

                    SqlDataAdapter da = new SqlDataAdapter();

                    DataSet ds = new DataSet();

                    da.SelectCommand = cmd;

                    da.Fill(ds);

                    return ds;

                }

            }

            catch

            {

                throw;

            }

        }

        /// <summary>

        /// 返回一个DataSet

        /// </summary>

        /// <param name="cmdType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param>

        /// <param name="cmdText">存储过程的名字或者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>return a dataset</returns>

        public static DataSet ExecuteDataSet(CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            return ExecuteDataSet(connectionString, cmdType, cmdText, commandParameters);

        }

        /// <summary>

        /// 返回一个DataSet

        /// </summary>

        /// <param name="cmdText">存储过程的名字</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>return a dataset</returns>

        public static DataSet ExecuteDataSetProducts(string cmdText, params SqlParameter[] commandParameters)

        {

            return ExecuteDataSet(connectionString, CommandType.StoredProcedure, cmdText, commandParameters);

        }

        /// <summary>

        /// 返回一个DataSet

        /// </summary>

        /// <param name="cmdText">T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>return a dataset</returns>

        public static DataSet ExecuteDataSetText(string cmdText, params SqlParameter[] commandParameters)

        {

            return ExecuteDataSet(connectionString, CommandType.Text, cmdText, commandParameters);

        }

        public static DataView ExecuteDataSet(string connectionString, string sortExpression, string direction, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            SqlCommand cmd = new SqlCommand();

            try

            {

                using (SqlConnection conn = new SqlConnection(connectionString))

                {

                    PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);

                    SqlDataAdapter da = new SqlDataAdapter();

                    DataSet ds = new DataSet();

                    da.SelectCommand = cmd;

                    da.Fill(ds);

                    DataView dv = ds.Tables[].DefaultView;

                    dv.Sort = sortExpression + " " + direction;

                    return dv;

                }

            }

            catch

            {

                throw;

            }

        }

        #endregion

        #region // ExecuteScalar方法

        /// <summary>

        /// 返回第一行的第一列

        /// </summary>

        /// <param name="cmdType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param>

        /// <param name="cmdText">存储过程的名字或者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>返回一个对象</returns>

        public static object ExecuteScalar(CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            return ExecuteScalar(SqlHelper.connectionString, cmdType, cmdText, commandParameters);

        }

        /// <summary>

        /// 返回第一行的第一列存储过程专用

        /// </summary>

        /// <param name="cmdText">存储过程的名字</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>返回一个对象</returns>

        public static object ExecuteScalarProducts(string cmdText, params SqlParameter[] commandParameters)

        {

            return ExecuteScalar(SqlHelper.connectionString, CommandType.StoredProcedure, cmdText, commandParameters);

        }

        /// <summary>

        /// 返回第一行的第一列Sql语句专用

        /// </summary>

        /// <param name="cmdText">者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>返回一个对象</returns>

        public static object ExecuteScalarText(string cmdText, params SqlParameter[] commandParameters)

        {

            return ExecuteScalar(SqlHelper.connectionString, CommandType.Text, cmdText, commandParameters);

        }

        /// <summary>

        /// Execute a SqlCommand that returns the first column of the first record against the database specified in the connection string

        /// using the provided parameters.

        /// </summary>

        /// <remarks>

        /// e.g.:

        ///  Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));

        /// </remarks>

        /// <param name="connectionString">一个有效的数据库连接字符串</param>

        /// <param name="cmdType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param>

        /// <param name="cmdText">存储过程的名字或者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>An object that should be converted to the expected type using Convert.To{Type}</returns>

        public static object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            SqlCommand cmd = new SqlCommand();

            using (SqlConnection connection = new SqlConnection(connectionString))

            {

                PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);

                object val = cmd.ExecuteScalar();

                cmd.Parameters.Clear();

                return val;

            }

        }

        /// <summary>

        /// Execute a SqlCommand that returns the first column of the first record against an existing database connection

        /// using the provided parameters.

        /// </summary>

        /// <remarks>

        /// e.g.:

        ///  Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));

        /// </remarks>

        /// <param name="connectionString">一个有效的数据库连接字符串</param>

        /// <param name="cmdType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param>

        /// <param name="cmdText">存储过程的名字或者 T-SQL 语句</param>

        /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param>

        /// <returns>An object that should be converted to the expected type using Convert.To{Type}</returns>

        public static object ExecuteScalar(SqlConnection connection, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            SqlCommand cmd = new SqlCommand();

            PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);

            object val = cmd.ExecuteScalar();

            cmd.Parameters.Clear();

            return val;

        }

        #endregion

        /// <summary>

        /// add parameter array to the cache

        /// </summary>

        /// <param name="cacheKey">Key to the parameter cache</param>

        /// <param name="cmdParms">an array of SqlParamters to be cached</param>

        public static void CacheParameters(string cacheKey, params SqlParameter[] commandParameters)

        {

            parmCache[cacheKey] = commandParameters;

        }

        /// <summary>

        /// Retrieve cached parameters

        /// </summary>

        /// <param name="cacheKey">key used to lookup parameters</param>

        /// <returns>Cached SqlParamters array</returns>

        public static SqlParameter[] GetCachedParameters(string cacheKey)

        {

            SqlParameter[] cachedParms = (SqlParameter[])parmCache[cacheKey];

            if (cachedParms == null)

                return null;

            SqlParameter[] clonedParms = new SqlParameter[cachedParms.Length];

            for (int i = , j = cachedParms.Length; i < j; i++)

                clonedParms = (SqlParameter)((ICloneable)cachedParms).Clone();

            return clonedParms;

        }

        /// <summary>

        /// 检查是否存在

        /// </summary>

        /// <param name="strSql">Sql语句</param>

        /// <param name="cmdParms">参数</param>

        /// <returns>bool结果</returns>

        public static bool Exists(string strSql, params SqlParameter[] cmdParms)

        {

            int cmdresult = Convert.ToInt32(ExecuteScalar(connectionString, CommandType.Text, strSql, cmdParms));

            if (cmdresult == )

            {

                return false;

            }

            else

            {

                return true;

            }

        }

    }

}