using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Data.SqlClient;using System.Data;namespace ConsoleApplication1{    class Program    {        static void Main(string[] args)        {            //用数据适配器填充DataSet类            string source = "server=(local) \\SQLEXPRESS;integrated security=true;database=Student";            SqlConnection con = new SqlConnection(source);            con.Open();            if (con.State == ConnectionState.Open)                Console.WriteLine("数据库连接成功！");            string select = "select * from customers";            SqlDataAdapter sda = new SqlDataAdapter(select, con);            DataSet ds = new DataSet();            sda.Fill(ds, "customers");//将数据适配器sda的数据（可以看成一个表）填充到ds中，数据（表）名为customers            foreach (DataRow x in ds.Tables["customers"].Rows)            {                Console.WriteLine("name:{0},id:{1}", x[0], x[1]);            }            DataSet ds2 = new DataSet();            SqlDataAdapter sda2 = new SqlDataAdapter();            sda2.SelectCommand = selectcommand(con);//sda2.SelectCommand:获取或设置一个 Transact-SQL 语句或存储过程，用于在数据源中选择记录            sda2.Fill(ds2, "customers2");//将数据适配器sda2的数据（可以看成一个表）填充到ds2中，数据（表）名为customers2            foreach (DataRow x in ds2.Tables["customers2"].Rows)            {                Console.WriteLine("name:{0},id:{1}", x[0], x[1]);            }        }        private static SqlCommand selectcommand(SqlConnection con)//自定义方法用于返回一个数据源记录        {            SqlCommand sc = new SqlCommand("selectstudent", con);            sc.CommandType = CommandType.StoredProcedure;            sc.UpdatedRowSource = UpdateRowSource.None;            sc.Parameters.AddWithValue("@id", 5);            sc.ExecuteNonQuery();            return sc;        }    }}

use Studentdrop procedure selectstudentgocreate procedure selectstudent(@id int)asselect *from Customerswhere id<=@id