using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Configuration;using System.Data.SqlClient;using System.Data;namespace progressdemo.DAL{    public static  class SQLHelper    {        //获得配置文件中的连接字符串        private static readonly string constr = ConfigurationManager.ConnectionStrings["sql"].ConnectionString;        /// <summary>        /// 执行insert、delete、update的方法        /// </summary>        /// <param name="sql"></param>        /// <param name="pms"></param>        /// <returns></returns>        public static int ExecteNonQuery(string sql, params SqlParameter[] pms)        {            //sqlconnection 表示连接数据库            using (SqlConnection con=new SqlConnection(constr))            {                using (SqlCommand cmd=new SqlCommand(sql,con))                {                    if (pms!=null)                    {                        cmd.Parameters.AddRange(pms);                    }                    con.Open();                    return cmd.ExecuteNonQuery();                }            }        }        /// <summary>        /// 返回首行首列        /// </summary>        /// <param name="sql"></param>        /// <param name="pms"></param>        /// <returns></returns>        public static object ExecuteScalar(string sql,params SqlParameter[] pms)        {            using (SqlConnection con=new SqlConnection(constr))            {                using (SqlCommand cmd=new SqlCommand(sql,con))                {                    if (pms!=null)                    {                        cmd.Parameters.AddRange(pms);                    }                    con.Open();                    return cmd.ExecuteScalar();                }            }        }        public static SqlDataReader ExecuteReader(string sql, params SqlParameter[] pms)        {            SqlConnection con=new SqlConnection(constr);             try             {            using (SqlCommand cmd=new SqlCommand(sql,con))            {                if (pms != null)                {                    cmd.Parameters.AddRange(pms);                }                con.Open();                //当调用ExecuteReader的时候如果传递的CommandBehavior.CloseConnection参数当reader关闭的时候                //sqlconnection也被关闭                SqlDataReader reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);                return reader;            }            }catch{              if(con!=null){                 con.Close();con.Disponse();
               }
               throw;            }        }        public static DataTable ExecuteDataTable(string sql, params SqlParameter[] pms)        {            SqlDataAdapter sqlAdaper = new SqlDataAdapter(sql, constr);            if (pms!=null)            {                sqlAdaper.SelectCommand.Parameters.AddRange(pms);            }            DataTable dt = new DataTable();            sqlAdaper.Fill(dt);            return dt;        }    }}