把查询结果赋值给实体类

config文件

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <startup> 
        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.7.2" />
    </startup>
    <connectionStrings>
        <add name="connString" connectionString="server=LIN;database=Excel;uid=sa;pwd=123456"/>
    </connectionStrings>
</configuration>

实体类：

namespace Models
{
    public class TestBackup
    {
        public int id { get; set; }
        public string name { get; set; }
        public int age { get; set; }
        public DateTime time { get; set; }
    }
}

数据模块：

namespace DAL
{
    public class TestBackupService
    {
        private static string connString= ConfigurationManager.ConnectionStrings["connString"].ToString();public static List<TestBackup> Select()
        {
            SqlConnection conn = new SqlConnection(connString) ;
            string sql = $"select * from testBackup";
            SqlCommand cmd= new SqlCommand(sql,conn);
            SqlDataReader count = null;
            try
            {
                conn.Open();
                count = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                List<TestBackup> testBackups= new List<TestBackup>();
//循环把查询赋给集合
                while (count.Read()) 
                {               
                    TestBackup testBackup = new TestBackup()
                    {
                    id = Convert.ToInt32(count["id"].ToString()),//重点
                    name = count["Tname"].ToString(),
                    age = Convert.ToInt32(count["age"].ToString()),
                    time = Convert.ToDateTime(count["datetime"].ToString())
                    };
                    testBackups.Add(testBackup);
                }
                return testBackups;
            }
            catch (Exception ex)
            {
                string msg = $"{DateTime.Now.ToString()}执行方法：public static SqlDataReader Select()错误";
                msg+= ex.Message;
                throw new Exception(msg);
                return null;
            }

        }
    }
}

业务类：

        public static void SelectBackup() {
            try
            {
                List<TestBackup> tsxts=TestBackupService.Select();
                foreach (TestBackup tst in tsxts)
                {
                    Console.WriteLine($"{tst.id}\t{tst.name}\t{tst.age}\t{tst.time}");
                }
            }catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }

            
        }