在 c# asp.net 中执行查询

using System;
using System.Data.SqlClient;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        string connectionString = "Data Source=your_server;Initial Catalog=your_database;User ID=your_username;Password=your_password";
        string queryString = "SELECT * FROM your_table";

        SqlConnection connection = new SqlConnection(connectionString);
        SqlCommand command = new SqlCommand(queryString, connection);

        try
        {
            connection.Open();
            SqlDataReader reader = command.ExecuteReader();

            while (reader.Read())
            {
                // 读取查询结果并处理
                string columnValue = reader["column_name"].ToString();
            }

            reader.Close();
        }
        catch (Exception ex)
        {
            // 处理异常
            Response.Write("Error: " + ex.Message);
        }
        finally
        {
            connection.Close();
        }
    }
}