能用存储过程的DBHelper类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Data.SqlClient;  

namespace Book.DAL
{
    public class DBHelper
    {
        private SqlConnection conn = null;
        private SqlCommand cmd = null;
        private SqlDataReader sdr = null;
        public DBHelper()
        {
            string connStr = "data Source=.;database=MYBOOKSHOP;uid=sa;pwd=123";
            conn = new SqlConnection(connStr);
        }  

        private SqlConnection GetConn()
        {
            if (conn.State == ConnectionState.Closed)
            {
                conn.Open();
            }
            return conn;
        }  

        /// <summary>
        ///  执行不带参数的增删改SQL语句或存储过程
        /// </summary>
        /// <param name="cmdText">增删改SQL语句或存储过程</param>
        /// <param name="ct">命令类型</param>
        /// <returns></returns>
        public int ExecuteNonQuery(string cmdText, CommandType ct)
        {
            int res;
            try
            {
                cmd = new SqlCommand(cmdText, GetConn());
                cmd.CommandType = ct;
                res = cmd.ExecuteNonQuery();
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                if (conn.State == ConnectionState.Open)
                {
                    conn.Close();
                }
            }
            return res;
        }  

        /// <summary>
        ///  执行带参数的增删改SQL语句或存储过程
        /// </summary>
        /// <param name="cmdText">增删改SQL语句或存储过程</param>
        /// <param name="ct">命令类型</param>
        /// <returns>int值</returns>
        public int ExecuteNonQuery(string cmdText, SqlParameter[] paras, CommandType ct)
        {
            int res;
            using (cmd = new SqlCommand(cmdText, GetConn()))
            {
                cmd.CommandType = ct;
                cmd.Parameters.AddRange(paras);
                res = cmd.ExecuteNonQuery();
            }
            return res;
        }  

        /// <summary>
        ///  执行查询SQL语句或存储过程
        /// </summary>
        /// <param name="cmdText">查询SQL语句或存储过程</param>
        /// <param name="ct">命令类型</param>
        /// <returns>Table值</returns>
        public DataTable ExecuteQuery(string cmdText, CommandType ct)
        {
            DataTable dt = new DataTable();
            cmd = new SqlCommand(cmdText, GetConn());
            cmd.CommandType = ct;
            using (sdr = cmd.ExecuteReader(CommandBehavior.CloseConnection))
            {
                dt.Load(sdr);
            }
            return dt;
        }  

        /// <summary>
        ///  执行带参数的查询SQL语句或存储过程
        /// </summary>
        /// <param name="cmdText">查询SQL语句或存储过程</param>
        /// <param name="paras">参数集合</param>
        /// <param name="ct">命令类型</param>
        /// <returns>Table值</returns>
        public DataTable ExecuteQuery(string cmdText, SqlParameter[] paras, CommandType ct)
        {
            DataTable dt = new DataTable();
            cmd = new SqlCommand(cmdText, GetConn());
            cmd.CommandType = ct;
            cmd.Parameters.AddRange(paras);
            using (sdr = cmd.ExecuteReader(CommandBehavior.CloseConnection))
            {
                dt.Load(sdr);
            }
            return dt;
        }  

        /// <summary>
        /// 执行带参数的Scalar查询
        /// </summary>
        /// <param name="cmdText">查询SQL语句或存储过程</param>
        /// <param name="paras">参数集合</param>
        /// <param name="ct">命令类型</param>
        /// <returns>一个int型值</returns>
        public int ExecuteCheck(string cmdText, SqlParameter[] paras, CommandType ct)
        {
            int result;
            using (cmd = new SqlCommand(cmdText, GetConn()))
            {
                cmd.CommandType = ct;
                cmd.Parameters.AddRange(paras);
                result = Convert.ToInt32(cmd.ExecuteScalar());
            }
            return result;
        }
    }
}  

用法

    // 判断用户名密码是否正确
            public bool CheckUser(string LoginId, string LoginPwd)
            {
                bool check = false;
                string cmdText = "procCheckUser";
                SqlParameter[] parm = new SqlParameter[]
                {
                    new SqlParameter("@LoginId",LoginId),
                    new SqlParameter("@LoginPwd",LoginPwd)
                };
                int one = dh.ExecuteCheck(cmdText, parm, CommandType.StoredProcedure);
                if (one > )
                {
                    return true;
                }
                return check;
            }  

            //根据图书类型显示该类型所有图书
            public DataTable SelectAllByType(int TypeId)
            {
                string cmdText = "procSelectAllByType";
                SqlParameter[] parm = new SqlParameter[]{
                    new SqlParameter("@TypeId",TypeId)
                    };
                dt = dh.ExecuteQuery(cmdText, parm, CommandType.StoredProcedure);
                return dt;
            }