SQL Server, Button_Click, C#

Help!  I am new to ASP and C#.  At click of button1 I want to execute a sql server Select query that will query the text entered by user in textbox1 and I want the result of the query to pop up in a message box.  Below is what I have so far in my aspx.cs.  Can some show me the rest?
 
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
    }
}
 
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