asp.net数据库查询代码

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

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            BindData();
        }
    }

    private void BindData()
    {
        string connectionString = ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString;
        using (SqlConnection con = new SqlConnection(connectionString))
        {
            con.Open();
            string query = "SELECT * FROM Employees";
            SqlCommand cmd = new SqlCommand(query, con);
            SqlDataReader reader = cmd.ExecuteReader();
            GridView1.DataSource = reader;
            GridView1.DataBind();
            reader.Close();
        }
    }
}

<connectionStrings>
    <add name="MyConnectionString" connectionString="Data Source=yourServerName;Initial Catalog=yourDatabaseName;User ID=yourUsername;Password=yourPassword;" providerName="System.Data.SqlClient" />
</connectionStrings>

using (SqlConnection con = new SqlConnection(connectionString))
{
    // 数据库操作
}