C#SQLServer数据库操作类

using System;
using System.Collections.Generic;
using System.Text;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Reflection;
 
namespace {namespace}.DBUtility
{
    public abstract class SqlHelper
    {
        /// <summary>
        /// 数据库连接字符串
        /// </summary>
        public static readonly string ConnectionString = ConfigurationManager.ConnectionStrings["SqlConnectionString"].ToString();
 
        #region 执行操作，返回表  +static DataTable ExcuteTable(string sql, CommandType type, params SqlParameter[] ps)
        /// <summary>
        /// 执行操作，返回表
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static DataTable ExcuteTable(string sql, CommandType type, params SqlParameter[] ps) {
            DataTable dt = new DataTable();
            SqlDataAdapter da = new SqlDataAdapter(sql, ConnectionString);
            da.SelectCommand.CommandType = type;
            da.SelectCommand.Parameters.AddRange(ps);
            da.Fill(dt);
            return dt;
        }
        #endregion
 
        #region 执行操作，返回DataSet表集合  +static DataSet ExcuteTable(string sql, CommandType type, params SqlParameter[] ps)
        /// <summary>
        /// 执行操作，返回表
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static DataSet ExcuteDataSet(string sql, CommandType type, params SqlParameter[] ps) {
            DataSet ds = new DataSet();
            SqlDataAdapter da = new SqlDataAdapter(sql, ConnectionString);
            da.SelectCommand.CommandType = type;
            da.SelectCommand.Parameters.AddRange(ps);
            da.Fill(ds);
            return ds;
        }
        #endregion
 
        #region 返回单个值的泛型版本  -static T ExcuteScalar<T>(string sql, params SqlParameter[] ps)
        /// <summary>
        /// 返回单个值的泛型版本
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="sql"></param>
        /// <param name="ps"></param>
        /// <returns></returns>
        public static T ExcuteScalar<T>(string sql, params SqlParameter[] ps) {
            using (SqlConnection conn = new SqlConnection(ConnectionString)) {
                conn.Open();
                SqlCommand comm = new SqlCommand(sql, conn);
                comm.Parameters.AddRange(ps);
                object obj = comm.ExecuteScalar(); //标识列返回的值的类型不是int而是decimal
                return default(T);
            }
        }
        #endregion
 
        #region 返回泛型集合  + static List<T> GetList<T>(DataTable dt)
        /// <summary>
        /// 返回泛型集合
        /// </summary>