如何在C#中从SQL查询字符串调用DAO

using System;
using System.Data;
using System.Data.SqlClient;

namespace DataAccessExample
{
    class Program
    {
        static void Main(string[] args)
        {
            // 创建数据库连接字符串
            string connectionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=UserName;Password=Password";

            // 创建SqlConnection对象
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                // 创建SQL查询字符串
                string queryString = "SELECT * FROM TableName";

                // 创建SqlCommand对象
                using (SqlCommand command = new SqlCommand(queryString, connection))
                {
                    try
                    {
                        // 打开数据库连接
                        connection.Open();

                        // 执行查询，并获取结果
                        using (SqlDataReader reader = command.ExecuteReader())
                        {
                            // 遍历查询结果
                            while (reader.Read())
                            {
                                // 提取数据
                                int id = (int)reader["ID"];
                                string name = (string)reader["Name"];

                                // 处理数据
                                Console.WriteLine("ID: {0}, Name: {1}", id, name);
                            }
                        }
                    }
                    catch (Exception ex)
                    {
                        Console.WriteLine("Error: " + ex.Message);
                    }
                    finally
                    {
                        // 关闭数据库连接
                        connection.Close();
                    }
                }
            }
        }
    }
}