实现事务处理.

        /**//// <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 ExecuteTransaction(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);
                }
            }
        }