003-SqlHelper.cs/Web.config

<?xml version="1.0" encoding="utf-8"?>

<!--
  有关如何配置 ASP.NET 应用程序的详细信息，请访问
  http://go.microsoft.com/fwlink/?LinkId=169433
  -->

<configuration>
    <system.web>
      <compilation debug="true" targetFramework="4.5" />
      <httpRuntime targetFramework="4.5" />
    </system.web>
  <connectionStrings>
    <add name="connStr" connectionString="server=.;database=web1;uid=sa;pwd=123"/>
  </connectionStrings>
</configuration>

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

namespace t3_TypeInfo
{
    public static class SqlHelper
    {
        private static string connStr =
            System.Configuration.ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;

        public static DataTable GetList()
        {
            using (SqlConnection conn=new SqlConnection(connStr))
            {
                string sql = "select * from typeinfo order by typeid desc";
                SqlDataAdapter sda=new SqlDataAdapter(sql,conn);
                DataTable dt=new DataTable();
                sda.Fill(dt);
                return dt;
            }
        }

        public static TypeInfo GetById(int id)
        {
            using (SqlConnection conn=new SqlConnection(connStr))
            {
                string sql = "select * from typeinfo where typeid=@id";
                SqlParameter p=new SqlParameter("@id",id);

                SqlCommand cmd=new SqlCommand(sql,conn);
                cmd.Parameters.Add(p);

                conn.Open();
                TypeInfo ti=new TypeInfo();
                SqlDataReader sdr = cmd.ExecuteReader();
                sdr.Read();
                ti.TypeId = Convert.ToInt32(sdr["TypeId"]);
                ti.TypeTitle = sdr["TypeTitle"].ToString();

                return ti;
            }
        }

        public static int Add(string title)
        {
            using (SqlConnection conn = new SqlConnection(connStr))
            {
                string sql = "insert into typeinfo values(@title)";
                SqlParameter p=new SqlParameter("@title",title);

                SqlCommand cmd=new SqlCommand(sql,conn);
                cmd.Parameters.Add(p);

                conn.Open();
                return cmd.ExecuteNonQuery();
            }
        }

        public static int Edit(TypeInfo ti)
        {
            using (SqlConnection conn=new SqlConnection(connStr))
            {
                string sql = "update typeinfo set typeTitle=@title where typeid=@id";
                SqlParameter[] ps =
                {
                    new SqlParameter("@id", ti.TypeId),
                    new SqlParameter("@title", ti.TypeTitle)
                };

                SqlCommand cmd=new SqlCommand(sql,conn);
                cmd.Parameters.AddRange(ps);

                conn.Open();
                return cmd.ExecuteNonQuery();
            }
        }

        public static int Remove(int id)
        {
            using (SqlConnection conn=new SqlConnection(connStr))
            {
                string sql = "delete from typeinfo where typeid=@id";
                SqlParameter p=new SqlParameter("@id",id);

                SqlCommand cmd=new SqlCommand(sql,conn);
                cmd.Parameters.Add(p);

                conn.Open();
                return cmd.ExecuteNonQuery();
            }
        }
    }
}