using System.Collections;
using System.Data;
using System.Data.SqlClient;

namespace Gs.Toolbox
{
    /// <summary>
    /// 数据访问类
    /// </summary>
    public abstract class DbHelperSQL
    {
        //数据库连接字符串(web.config来配置)   
        public static readonly string strConn = AppSettingsHelper.getValueByKey("ConnectionStrings");
        public DbHelperSQL()
        {

        }
        #region 公用方法
        /// <summary>
        /// 取到最大字段值
        /// </summary>
        /// <param name="FieldName"></param>
        /// <param name="TableName"></param>
        /// <returns></returns>
        public static int GetMaxID(string FieldName, string TableName)
        {
            string strsql = "select max(" + FieldName + ") from " + TableName;
            object obj = GetSingle(strsql);
            if (obj == null)
            {
                return 0;
            }
            else
            {
                return int.Parse(obj.ToString());
            }
        }
        /// <summary>
        /// 是否存在某条记录
        /// </summary>
        /// <param name="strSql"></param>
        /// <param name="cmdParms"></param>
        /// <returns></returns>
        public static bool Exists(string strSql, params SqlParameter[] cmdParms)
        {
            object obj = GetSingle(strSql, cmdParms);
            int cmdresult;
            if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
            {
                cmdresult = 0;
            }
            else
            {
                cmdresult = int.Parse(obj.ToString());
            }
            if (cmdresult == 0)
            {
                return false;
            }
            else
            {
                return true;
            }
        }
        #endregion

        #region  执行简单SQL语句
        /// <summary>   
        /// 执行SQL语句，返回影响的记录数   
        /// </summary>   
        /// <param name="SQLString">SQL语句</param>   
        /// <returns>影响的记录数</returns>   
        public static int ExecuteSql(string SQLString)
        {
            using (SqlConnection connection = new SqlConnection(strConn))
            {
                using (SqlCommand cmd = new SqlCommand(SQLString, connection))
                {
                    try
                    {
                        connection.Open();
                        int rows = cmd.ExecuteNonQuery();
                        return rows;
                    }
                    catch (System.Data.SqlClient.SqlException E)
                    {
                        connection.Close();
                        throw new Exception(E.Message);
                    }
                }
            }
        }
        /// <summary>   
        /// 执行多条SQL语句，实现数据库事务。   
        /// </summary>   
        /// <param name="SQLStringList">多条SQL语句</param>        
        public static void ExecuteSqlTran(ArrayList SQLStringList)
        {
            using (SqlConnection conn = new SqlConnection(strConn))
            {
                conn.Open();
                SqlCommand cmd = new SqlCommand();
                cmd.Connection = conn;
                SqlTransaction tx = conn.BeginTransaction();
                cmd.Transaction = tx;
                try
                {
                    for (int n = 0; n < SQLStringList.Count; n++)
                    {
                        string strsql = SQLStringList[n].ToString();
                        if (strsql.Trim().Length > 1)
                        {
                            cmd.CommandText = strsql;
                            cmd.ExecuteNonQuery();
                        }
                    }
                    tx.Commit();
                }
                catch (System.Data.SqlClient.SqlException E)
                {
                    tx.Rollback();
                    throw new Exception(E.Message);
                }
            }
        }
        /// <summary>   
        /// 执行带一个存储过程参数的的SQL语句。   
        /// </summary>   
        /// <param name="SQLString">SQL语句</param>   
        /// <param name="content">参数内容,比如一个字段是格式复杂的文章，有特殊符号，可以通过这个方式添加</param>   
        /// <returns>影响的记录数</returns>   
        public static int ExecuteSql(string SQLString, string content)
        {
            using (SqlConnection connection = new SqlConnection(strConn))
            {
                SqlCommand cmd = new SqlCommand(SQLString, connection);
                System.Data.SqlClient.SqlParameter myParameter = new System.Data.SqlClient.SqlParameter("@content", SqlDbType.NText);
                myParameter.Value = content;
                cmd.Parameters.Add(myParameter);
                try
                {
                    connection.Open();
                    int rows = cmd.ExecuteNonQuery();
                    return rows;
                }
                catch (System.Data.SqlClient.SqlException E)
                {
                    throw new Exception(E.Message);
                }
                finally
                {
                    cmd.Dispose();
                    connection.Close();
                }
            }
        }
        /// <summary>   
        /// 向数据库里插入图像格式的字段(和上面情况类似的另一种实例)   
        /// </summary>   
        /// <param name="strSQL">SQL语句</param>   
        /// <param name="fs">图像字节,数据库的字段类型为image的情况</param>   
        /// <returns>影响的记录数</returns>   
        public static int ExecuteSqlInsertImg(string strSQL, byte[] fs)
        {
            using (SqlConnection connection = new SqlConnection(strConn))
            {
                SqlCommand cmd = new SqlCommand(strSQL, connection);
                System.Data.SqlClient.SqlParameter myParameter = new System.Data.SqlClient.SqlParameter("@fs", SqlDbType.Image);
                myParameter.Value = fs;
                cmd.Parameters.Add(myParameter);
                try
                {
                    connection.Open();
                    int rows = cmd.ExecuteNonQuery();
                    return rows;
                }
                catch (System.Data.SqlClient.SqlException E)
                {
                    throw new Exception(E.Message);
                }
                finally
                {
                    cmd.Dispose();
                    connection.Close();
                }
            }
        }
        /// <summary>   
        /// 执行一条计算查询结果语句，返回查询结果（object）。   
        /// </summary>   
        /// <param name="SQLString">计算查询结果语句</param>   
        /// <returns>查询结果（object）</returns>   
        public static object GetSingle(string SQLString)
        {
            using (SqlConnection connection = new SqlConnection(strConn))
            {
                using (SqlCommand cmd = new SqlCommand(SQLString, connection))
                {
                    try
                    {
                        connection.Open();
                        object obj = cmd.ExecuteScalar();
                        if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                        {
                            return null;
                        }
                        else
                        {
                            return obj;
                        }
                    }
                    catch (System.Data.SqlClient.SqlException e)
                    {
                        connection.Close();
                        throw new Exception(e.Message);
                    }
                }
            }
        }
        /// <summary>   
        /// 执行查询语句，返回SqlDataReader   
        /// </summary>   
        /// <param name="strSQL">查询语句</param>   
        /// <returns>SqlDataReader</returns>   
        public static SqlDataReader ExecuteReader(string strSQL)
        {
            SqlConnection connection = new SqlConnection(strConn);
            SqlCommand cmd = new SqlCommand(strSQL, connection);
            try
            {
                connection.Open();
                SqlDataReader myReader = cmd.ExecuteReader();
                return myReader;
            }
            catch (System.Data.SqlClient.SqlException e)
            {
                throw new Exception(e.Message);
            }

        }
        /// <summary>   
        /// 执行查询语句，返回DataSet   
        /// </summary>   
        /// <param name="SQLString">查询语句</param>   
        /// <returns>DataSet</returns>   
        public static DataSet Query(string SQLString)
        {
            using (SqlConnection connection = new SqlConnection(strConn))
            {
                DataSet ds = new DataSet();
                try
                {
                    connection.Open();
                    SqlDataAdapter command = new SqlDataAdapter(SQLString, connection);
                    command.Fill(ds, "ds");
                }
                catch (System.Data.SqlClient.SqlException ex)
                {
                    throw new Exception(ex.Message);
                }
                return ds;
            }
        }
        #endregion

        #region 执行带参数的SQL语句
        /// <summary>   
        /// 执行SQL语句，返回影响的记录数   
        /// </summary>   
        /// <param name="SQLString">SQL语句</param>   
        /// <returns>影响的记录数</returns>   
        public static int ExecuteSql(string SQLString, params SqlParameter[] cmdParms)
        {
            using (SqlConnection connection = new SqlConnection(strConn))
            {
                using (SqlCommand cmd = new SqlCommand())
                {
                    try
                    {
                        PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                        int rows = cmd.ExecuteNonQuery();
                        cmd.Parameters.Clear();
                        return rows;
                    }
                    catch (System.Data.SqlClient.SqlException E)
                    {
                        throw new Exception(E.Message);
                    }
                }
            }
        }
        /// <summary>   
        /// 执行多条SQL语句，实现数据库事务。   
        /// </summary>   
        /// <param name="SQLStringList">SQL语句的哈希表（key为sql语句，value是该语句的SqlParameter[]）</param>   
        public static void ExecuteSqlTran(Hashtable SQLStringList)
        {
            using (SqlConnection conn = new SqlConnection(strConn))
            {
                conn.Open();
                using (SqlTransaction trans = conn.BeginTransaction())
                {
                    SqlCommand cmd = new SqlCommand();
                    try
                    {
                        //循环   
                        foreach (DictionaryEntry myDE in SQLStringList)
                        {
                            string cmdText = myDE.Key.ToString();
                            SqlParameter[] cmdParms = (SqlParameter[])myDE.Value;
                            PrepareCommand(cmd, conn, trans, cmdText, cmdParms);
                            int val = cmd.ExecuteNonQuery();
                            cmd.Parameters.Clear();

                            //trans.Commit();
                        }
                        trans.Commit();
                    }
                    catch
                    {
                        trans.Rollback();
                        throw;
                    }
                }
            }
        }
        /// <summary>   
        /// 执行多条SQL语句，实现数据库事务。   
        /// </summary>   
        /// <param name="SQLStringList">SQL语句的哈希表（key为sql语句，value是该语句的SqlParameter[]）</param>   
        public static int ExecuteSqlTranRtn(Hashtable SQLStringList)
        {
            int d = 0;
            using (SqlConnection conn = new SqlConnection(strConn))
            {
                conn.Open();
                using (SqlTransaction trans = conn.BeginTransaction())
                {
                    SqlCommand cmd = new SqlCommand();
                    try
                    {
                        //循环   
                        foreach (DictionaryEntry myDE in SQLStringList)
                        {
                            string cmdText = myDE.Key.ToString();
                            SqlParameter[] cmdParms = (SqlParameter[])myDE.Value;
                            PrepareCommand(cmd, conn, trans, cmdText, cmdParms);
                            int val = cmd.ExecuteNonQuery();
                            d = d + val;
                            cmd.Parameters.Clear();

                            //trans.Commit();
                        }
                        trans.Commit();
                    }
                    catch
                    {
                        trans.Rollback();
                        throw;
                    }
                }
            }
            return d;
        }
        /// <summary>   
        /// 执行多条SQL语句，实现数据库事务   
        /// </summary>   
        /// <param name="SQLStringList">SQL语句的哈希表（key为标识，value是该语句的SqlParameter[]）</param>   
        public static void ExecuteSqlTran(string sqltxt, Hashtable SQLStringList)
        {
            using (SqlConnection conn = new SqlConnection(strConn))
            {
                conn.Open();
                using (SqlTransaction trans = conn.BeginTransaction())
                {
                    SqlCommand cmd = new SqlCommand();
                    try
                    {
                        //循环   
                        foreach (DictionaryEntry myDE in SQLStringList)
                        {
                            string cmdText = sqltxt;
                            SqlParameter[] cmdParms = (SqlParameter[])myDE.Value;
                            PrepareCommand(cmd, conn, trans, cmdText, cmdParms);
                            int val = cmd.ExecuteNonQuery();
                            cmd.Parameters.Clear();
                        }
                        trans.Commit();
                    }
                    catch
                    {
                        trans.Rollback();
                        throw;
                    }
                }
            }
        }
        /// <summary>   
        /// 执行一条计算查询结果语句，返回查询结果（object）。   
        /// </summary>   
        /// <param name="SQLString">计算查询结果语句</param>   
        /// <returns>查询结果（object）</returns>   
        public static object GetSingle(string SQLString, params SqlParameter[] cmdParms)
        {
            using (SqlConnection connection = new SqlConnection(strConn))
            {
                using (SqlCommand cmd = new SqlCommand())
                {
                    try
                    {
                        PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                        object obj = cmd.ExecuteScalar();
                        cmd.Parameters.Clear();
                        if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                        {
                            return null;
                        }
                        else
                        {
                            return obj;
                        }
                    }
                    catch (System.Data.SqlClient.SqlException e)
                    {
                        throw new Exception(e.Message);
                    }
                }
            }
        }
        /// <summary>   
        /// 执行查询语句，返回SqlDataReader   
        /// </summary>   
        /// <param name="strSQL">查询语句</param>   
        /// <returns>SqlDataReader</returns>   
        public static SqlDataReader ExecuteReader(string SQLString, params SqlParameter[] cmdParms)
        {
            SqlConnection connection = new SqlConnection(strConn);
            SqlCommand cmd = new SqlCommand();
            try
            {
                PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                SqlDataReader myReader = cmd.ExecuteReader();
                cmd.Parameters.Clear();
                return myReader;
            }
            catch (System.Data.SqlClient.SqlException e)
            {
                throw new Exception(e.Message);
            }

        }
        /// <summary>   
        /// 执行查询语句，返回DataSet   
        /// </summary>   
        /// <param name="SQLString">查询语句</param>   
        /// <returns>DataSet</returns>   
        public static DataSet Query(string SQLString, params SqlParameter[] cmdParms)
        {
            using (SqlConnection connection = new SqlConnection(strConn))
            {
                SqlCommand cmd = new SqlCommand();
                PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                using (SqlDataAdapter da = new SqlDataAdapter(cmd))
                {
                    DataSet ds = new DataSet();
                    try
                    {
                        da.Fill(ds, "ds");
                        cmd.Parameters.Clear();
                    }
                    catch (System.Data.SqlClient.SqlException ex)
                    {
                        throw new Exception(ex.Message);
                    }
                    return ds;
                }
            }
        }

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

        //    if (conn.State != ConnectionState.Open)
        //        conn.Open();
        //    cmd.Connection = conn;
        //    cmd.CommandText = cmdText;
        //    if (trans != null)
        //        cmd.Transaction = trans;
        //    cmd.CommandType = CommandType.Text;//cmdType;
        //    if (cmdParms != null)
        //    {
        //        foreach (SqlParameter parameter in cmdParms)
        //        {
        //            if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) &&
        //                (parameter.Value == null))
        //            {
        //                parameter.Value = DBNull.Value;
        //            }
        //            cmd.Parameters.Add(parameter);
        //        }
        //    }
        //}
        private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, string cmdText, SqlParameter[] cmdParms)
        {
            if (conn.State != ConnectionState.Open)
                conn.Open();
            cmd.Connection = conn;
            cmd.CommandText = cmdText;
            if (trans != null)
                cmd.Transaction = trans;
            cmd.CommandType = CommandType.Text;//cmdType;   
            if (cmdParms != null)
            {
                foreach (SqlParameter parm in cmdParms)
                {
                    //cmd.Parameters.Add(parm);
                    if ((parm.Direction == ParameterDirection.InputOutput || parm.Direction == ParameterDirection.Input) &&
                        (parm.Value == null))
                    {
                        parm.Value = DBNull.Value;
                    }
                    cmd.Parameters.Add(parm);
                }
            }
        }
        #endregion

        #region 存储过程操作
        /// <summary>   
        /// 执行存储过程   
        /// </summary>   
        /// <param name="storedProcName">存储过程名</param>   
        /// <param name="parameters">存储过程参数</param>   
        /// <returns>SqlDataReader</returns>   
        public static SqlDataReader RunProcedure(string storedProcName, IDataParameter[] parameters)
        {
            SqlConnection connection = new SqlConnection(strConn);
            SqlDataReader returnReader;
            connection.Open();
            SqlCommand command = BuildQueryCommand(connection, storedProcName, parameters);
            command.CommandType = CommandType.StoredProcedure;
            returnReader = command.ExecuteReader();
            return returnReader;
        }
        /// <summary>   
        /// 执行带输出参数的存储过程   
        /// </summary>   
        /// <param name="storedProcName">存储过程名</param>   
        /// <param name="parameters">存储过程参数,OutName 输出参数的名字（如果是多个以@为分割符）</param>   
        /// <returns>string(以|分割的输出参数的值)</returns>   
        public static string RunProcedureOut(string storedProcName, IDataParameter[] parameters, string outName)
        {
            SqlConnection connection = new SqlConnection(strConn);
            string returnstring = string.Empty;
            connection.Open();
            SqlCommand command = BuildQueryCommand(connection, storedProcName, parameters);
            command.CommandType = CommandType.StoredProcedure;
            command.ExecuteNonQuery();
            string str = string.Empty;
            //解析穿过来的参数   
            string[] Arraystr = outName.Split('|');
            foreach (string st in Arraystr)
            {
                string a = st.ToString();
                if (str == string.Empty)
                {
                    str = command.Parameters[a].Value.ToString();
                }
                else
                {
                    str = str + "|" + command.Parameters[a].Value.ToString();
                }
            }
            return str;
        }
        /// <summary>   
        /// 执行存储过程   
        /// </summary>   
        /// <param name="storedProcName">存储过程名</param>   
        /// <param name="parameters">存储过程参数</param>   
        /// <param name="tableName">DataSet结果中的表名</param>   
        /// <returns>DataSet</returns>   
        public static DataSet RunProcedure(string storedProcName, IDataParameter[] parameters, string tableName)
        {
            using (SqlConnection connection = new SqlConnection(strConn))
            {
                DataSet dataSet = new DataSet();
                connection.Open();
                SqlDataAdapter sqlDA = new SqlDataAdapter();
                sqlDA.SelectCommand = BuildQueryCommand(connection, storedProcName, parameters);
                sqlDA.Fill(dataSet, tableName);
                connection.Close();
                return dataSet;
            }
        }
        /// <summary>   
        /// 构建 SqlCommand 对象(用来返回一个结果集，而不是一个整数值)   
        /// </summary>   
        /// <param name="connection">数据库连接</param>   
        /// <param name="storedProcName">存储过程名</param>   
        /// <param name="parameters">存储过程参数</param>   
        /// <returns>SqlCommand</returns>   
        private static SqlCommand BuildQueryCommand(SqlConnection connection, string storedProcName, IDataParameter[] parameters)
        {
            SqlCommand command = new SqlCommand(storedProcName, connection);
            command.CommandType = CommandType.StoredProcedure;
            foreach (SqlParameter parameter in parameters)
            {
                command.Parameters.Add(parameter);
            }
            return command;
        }
        /// <summary>   
        /// 执行存储过程，返回影响的行数         
        /// </summary>   
        /// <param name="storedProcName">存储过程名</param>   
        /// <param name="parameters">存储过程参数</param>   
        /// <param name="rowsAffected">影响的行数</param>   
        /// <returns></returns>   
        public static int RunProcedure(string storedProcName, IDataParameter[] parameters, out int rowsAffected)
        {
            using (SqlConnection connection = new SqlConnection(strConn))
            {
                int result;
                connection.Open();
                SqlCommand command = BuildIntCommand(connection, storedProcName, parameters);
                rowsAffected = command.ExecuteNonQuery();
                result = (int)command.Parameters["ReturnValue"].Value;
                //Connection.Close();   
                return result;
            }
        }
        /// <summary>   
        /// 执行存储过程，返回影响行数   
        /// </summary>   
        /// <param name="storedProcName">string类型存储过程名</param>   
        /// <param name="parameters">SqlParameters[]存储过程参数</param>   
        /// <returns>int 影响行数</returns>   
        public static int RunProcedure_NonQuery(string storedProcName, IDataParameter[] parameters)
        {
            using (SqlConnection connection = new SqlConnection(strConn))
            {
                connection.Open();
                SqlCommand command = BuildQueryCommand(connection, storedProcName, parameters);
                return (command.ExecuteNonQuery());
            }
        }
        /// <summary>   
        /// 创建 SqlCommand 对象实例(用来返回一个整数值)      
        /// </summary>   
        /// <param name="storedProcName">存储过程名</param>   
        /// <param name="parameters">存储过程参数</param>   
        /// <returns>SqlCommand 对象实例</returns>   
        private static SqlCommand BuildIntCommand(SqlConnection connection, string storedProcName, IDataParameter[] parameters)
        {
            SqlCommand command = BuildQueryCommand(connection, storedProcName, parameters);
            command.Parameters.Add(new SqlParameter("ReturnValue",
                SqlDbType.Int, 4, ParameterDirection.ReturnValue,
                false, 0, 0, string.Empty, DataRowVersion.Default, null));
            return command;
        }
        #endregion
    }
}