Expected class, delegate, enum, interface, or struct
<p>I'm new to ASP.NET and trying to retrieve data set from database but I've got an error as the title says</p>

<p>Here is the code, What's the problem?</p>

<pre><code>using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;

public partial class Admin_addNode : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        var category = new category();
        DataSet ds = new DataSet();
        ds = category.getNode();
        DataTable tbl = ds.Tables[0];
        for (int i = 0; i &lt; tbl.Rows.Count; i++)
        {
        DataRow myRow = tbl.Rows[i];
        string MyValue = myRow["title"].ToString();
        Response.Write(MyValue);
        }
    } 


    }
    protected void Button1_Click(object sender, EventArgs e)
    {

    }
}
</code></pre>

<p>protected void Button1_Click in which "void" is red underlined in vwd</p>
