using System;
using System.Collections;
using System.Collections.Specialized;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;

namespace WebBee
{
        /// <summary>
        /// Copyright (C) 2006-2008 Itung
        /// 数据访问基础类(基于SQLServer)
        /// 用户可以修改满足自己项目的需要。
        /// </summary>
        public abstract class DBHelper
        {
            //数据库连接字符串(web.config来配置)
            //<add key="ConnectionString" value="server=127.0.0.1;database=DATABASE;uid=sa;pwd=" />

           // protected static string connectionString = @"Data Source=UMSERVER-01\UMESSAGE;Initial Catalog=UMsgTemp;user ;
            protected static string connectionString = " Server=.;DataBase=pubs;User ;
           

            #region 公用方法
            /// <summary>
            /// 获得最大值
            /// </summary>
            /// <param >字段名称</param>
            /// <param >表名</param>
            /// <returns>最大值</returns>
            public static int GetMaxID(string FieldName, string TableName)
            {
                string strsql = "select max(" + FieldName + ")+1 from " + TableName;
                object obj = GetSingle(strsql);
                if (obj == null)
                {
                    return 1;
                }
                else
                {
                    return int.Parse(obj.ToString());
                }
            }
            /// <summary>
            /// 判断是否存在
            /// </summary>
            /// <param >SQL</param>
            /// <param >参数</param>
            /// <returns>bool</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 >SQL语句</param>
            /// <returns>影响的记录数</returns>
            public static int ExecuteSql(string SQLString)
            {
                using (SqlConnection connection = new SqlConnection(connectionString))
                {
                    using (SqlCommand cmd = new SqlCommand(SQLString, connection))
                    {
                        try
                        {
                            connection.Open();
                            int rows = cmd.ExecuteNonQuery();
                            connection.Close();
                            return rows;
                        }
                        catch (System.Data.SqlClient.SqlException E)
                        {
                            connection.Close();

                            throw new Exception(E.Message);
                        }
                        finally
                        {
                            connection.Close();

                        }
                    }
                }
            }

            /// <summary>
            /// 执行多条SQL语句，实现数据库事务。
            /// </summary>
            /// <param >多条SQL语句</param> 
            public static void ExecuteSqlTran(ArrayList SQLStringList)
            {
                using (SqlConnection conn = new SqlConnection(connectionString))
                {
                    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 >SQL语句</param>
            /// <param >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(connectionString))
                {
                    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 >SQL语句</param>
            /// <param >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(connectionString))
                {
                    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 >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(connectionString))
                {
                    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 >查询语句</param>
            /// <returns>SqlDataReader</returns>
            public static SqlDataReader ExecuteReader(string strSQL)
            {
                SqlConnection connection = new SqlConnection(connectionString);
                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 >查询语句</param>
            /// <returns>DataSet</returns>
            public static DataSet Query(string SQLString)
            {
                using (SqlConnection connection = new SqlConnection(connectionString))
                {
                    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 >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(connectionString))
                {
                    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 >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(connectionString))
                {
                    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();
                            }
                        }
                        catch (Exception e)
                        {
                            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 >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(connectionString))
                {
                    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 >查询语句</param>
            /// <returns>SqlDataReader</returns>
            public static SqlDataReader ExecuteReader(string SQLString, params SqlParameter[] cmdParms)
            {
                SqlConnection connection = new SqlConnection(connectionString);
                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 >查询语句</param>
            /// <returns>DataSet</returns>
            public static DataSet Query(string SQLString, params SqlParameter[] cmdParms)
            {
                using (SqlConnection connection = new SqlConnection(connectionString))
                {
                    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 parm in cmdParms)
                        cmd.Parameters.Add(parm);
                }
            }

            #endregion

            #region 存储过程操作
            /// <summary>
            /// 执行存储过程
            /// </summary>
            /// <param >存储过程名</param>
            /// <param >存储过程参数</param>
            /// <returns>SqlDataReader</returns>
            public static SqlDataReader RunProcedure(string storedProcName, IDataParameter[] parameters)
            {
                SqlConnection connection = new SqlConnection(connectionString);
                SqlDataReader returnReader;
                connection.Open();
                SqlCommand command = BuildQueryCommand(connection, storedProcName, parameters);
                command.CommandType = CommandType.StoredProcedure;
                returnReader = command.ExecuteReader();
                return returnReader;
            }

            /// <summary>
            /// 执行存储过程
            /// </summary>
            /// <param >存储过程名</param>
            /// <param >存储过程参数</param>
            /// <param >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(connectionString))
                {
                    DataSet dataSet = new DataSet();
                    try
                    {
                        connection.Open();
                        SqlDataAdapter sqlDA = new SqlDataAdapter();
                        sqlDA.SelectCommand = BuildQueryCommand(connection, storedProcName, parameters);
                        sqlDA.Fill(dataSet, tableName);
                        connection.Close();
                    }
                    catch (Exception e)
                    {
                     
                    }
                    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 >数据库连接</param>
            /// <param >存储过程名</param>
            /// <param >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 >存储过程名</param>
            /// <param >存储过程参数</param>
            /// <param >影响的行数</param>
            /// <returns></returns>
            public static int RunProcedure(string storedProcName, IDataParameter[] parameters, out int rowsAffected)
            {
                using (SqlConnection connection = new SqlConnection(connectionString))
                {
                    int result;
                    connection.Open();
                    SqlCommand command = BuildIntCommand(connection, storedProcName, parameters);
                    rowsAffected = command.ExecuteNonQuery();
                    result = (int)command.Parameters["ReturnValue"].Value;
                    //Connection.Close();
                    return result;

                }
            }

            /// <summary>
            /// 创建 SqlCommand 对象实例(用来返回一个整数值)
            /// </summary>
            /// <param >存储过程名</param>
            /// <param >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

        }
   
}