操作数据库帮助类

1、sqlserver

    public class SqlHelper
    {
        private static SqlConnection connection;

        public static SqlConnection Connection
        {
            get
            {
                string connectionString = ConfigurationManager.AppSettings["connStr"];
                if (connection == null)
                {
                    connection = new SqlConnection(connectionString);
                    connection.Open();
                }
                else if (connection.State == System.Data.ConnectionState.Closed)
                {
                    connection.Open();
                }
                else if (connection.State == System.Data.ConnectionState.Broken)
                {
                    connection.Close();
                    connection.Open();
                }
                return connection;
            }
        }

        /// <summary>  
        /// 执行一个增删改存储过程(有参)  
        /// </summary>  
        /// <param name="procName">存储过程名字</param>  
        /// <param name="values">参数列表</param>  
        /// <returns>影响行数</returns>  
        public static int ExecuteProc(string procName, params SqlParameter[] values)
        {
            SqlCommand cmd = new SqlCommand();
            cmd.Connection = Connection;
            cmd.CommandText = procName;
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.AddRange(values);
            return cmd.ExecuteNonQuery();
        }
        /// <summary>  
        /// 执行一个查询无参存储过程，要关闭  
        /// </summary>  
        /// <param name="procName">存储过程名字</param>  
        /// <returns>SqlDataReader</returns>  
        public static SqlDataReader ExecuteProcSelect(string procName)
        {
            SqlCommand cmd = new SqlCommand();
            cmd.Connection = Connection;
            cmd.CommandText = procName;
            cmd.CommandType = CommandType.StoredProcedure;
            return cmd.ExecuteReader();
        }
        /// <summary>  
        /// 执行一个带参查询存储过程,注意要关闭   
        /// </summary>  
        /// <param name="procName">存储过程名字</param>  
        /// <param name="values">参数列表</param>  
        /// <returns>SqlDataReader</returns>  
        public static SqlDataReader ExecuteProcSelect(string procName, params SqlParameter[] values)
        {
            SqlCommand cmd = new SqlCommand();
            cmd.Connection = Connection;
            cmd.CommandText = procName;
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.AddRange(values);
            return cmd.ExecuteReader();
        }
        /// <summary>  
        /// 执行一个无参增删改存储过程  
        /// </summary>  
        /// <param name="procName">存储过程名字</param>  
        /// <returns>影响行数</returns>  
        public static int ExecuteProc(string procName)
        {
            SqlCommand cmd = new SqlCommand();
            cmd.Connection = Connection;
            cmd.CommandText = procName;
            cmd.CommandType = CommandType.StoredProcedure;
            return cmd.ExecuteNonQuery();
        }
        /// <summary>  
        /// 执行一个(无参)增删改语句  
        /// </summary>  
        /// <param name="safeSql">语句</param>  
        /// <returns>影响行数</returns>  
        public static int ExecuteCommand(string safeSql)
        {
            SqlCommand cmd = new SqlCommand(safeSql, Connection);
            int result = cmd.ExecuteNonQuery();
            return result;
        }
        /// <summary>  
        /// 执行一个有参增删改操作  
        /// </summary>  
        /// <param name="sql">语句</param>  
        /// <param name="values">参数</param>  
        /// <returns>影响行数 </returns>  
        public static int ExecuteCommand(string sql, params SqlParameter[] values)
        {
            SqlCommand cmd = new SqlCommand(sql, Connection);
            cmd.Parameters.AddRange(values);
            return cmd.ExecuteNonQuery();
        }
        /// <summary>  
        /// 查询第一行第一列数据（无参）（返回的是什么类型就转换成什么类型）  
        /// </summary>  
        /// <param name="safeSql">语句</param>  
        /// <returns>object</returns>  
        public static object GetScalar(string safeSql)
        {
            SqlCommand cmd = new SqlCommand(safeSql, Connection);
            return cmd.ExecuteScalar();
        }

        /// <summary>  
        /// 查询第一行第一列数据（有参）（返回的是什么类型就转换成什么类型）  
        /// </summary>  
        /// <param name="values">参数</param>  
        /// <returns>object</returns>  
        public static object GetScalar(string safeSql, params SqlParameter[] values)
        {
            SqlCommand cmd = new SqlCommand(safeSql, Connection);
            cmd.Parameters.AddRange(values);
            return cmd.ExecuteScalar();
        }
        /// <summary>  
        /// 返回一个SqlDataReader（注意要关闭）  
        /// </summary>  
        /// <param name="safeSql">语句</param>  
        /// <returns>SqlDataReader</returns>  
        public static SqlDataReader GetReader(string safeSql)
        {
            SqlCommand cmd = new SqlCommand(safeSql, Connection);
            SqlDataReader reader = cmd.ExecuteReader();
            return reader;
        }
        /// <summary>  
        /// 返回int  
        /// </summary>  
        /// <param name="sql"></param>  
        /// <param name="values"></param>  
        /// <returns></returns>  
        public static int GetScalarInt(string sql, params SqlParameter[] values)
        {
            SqlCommand cmd = new SqlCommand(sql, Connection);
            cmd.Parameters.AddRange(values);
            return Convert.ToInt32(cmd.ExecuteScalar());
        }
        /// <summary>  
        /// 返回string  
        /// </summary>  
        /// <param name="sql"></param>  
        /// <param name="values"></param>  
        /// <returns></returns>  
        public static string GetScalarString(string sql, params SqlParameter[] values)
        {
            SqlCommand cmd = new SqlCommand(sql, Connection);
            cmd.Parameters.AddRange(values);
            return Convert.ToString(cmd.ExecuteScalar());
        }

        /// <summary>  
        /// 返回一个有参SqlDataReader（注意要关闭）  
        /// </summary>  
        /// <param name="sql">语句</param>  
        /// <param name="values">参数</param>  
        /// <returns>SqlDataReader</returns>  
        public static SqlDataReader GetReader(string sql, params SqlParameter[] values)
        {
            SqlCommand cmd = new SqlCommand(sql, Connection);
            cmd.Parameters.AddRange(values);
            SqlDataReader reader = cmd.ExecuteReader();
            return reader;
        }

        /// <summary>  
        /// 返回一个Datatable（无参）  
        /// </summary>  
        /// <param name="safeSql">语句</param>  
        /// <returns>DataTable</returns>  
        public static DataTable GetDataSet(string safeSql)
        {
            DataSet ds = new DataSet();
            SqlCommand cmd = new SqlCommand(safeSql, Connection);
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            da.Fill(ds);
            return ds.Tables[0];
        }

        /// <summary>  
        /// 返回一个Datatable（有参）  
        /// </summary>  
        /// <param name="sql">语句</param>  
        /// <param name="values">参数</param>  
        /// <returns>DataTable</returns>  
        public static DataTable GetDataSet(string sql, params SqlParameter[] values)
        {
            DataSet ds = new DataSet();
            SqlCommand cmd = new SqlCommand(sql, Connection);
            cmd.Parameters.AddRange(values);
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            da.Fill(ds);
            return ds.Tables[0];
        }

        /// <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)
        {
            SqlCommand cmd = new SqlCommand();
            cmd.Connection = Connection;
            SqlTransaction tx = Connection.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);
            }
        }
    }