how to caputure user control button click event in aspx page

using System;

using System.Data;

using System.Configuration;

using System.Collections;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;



public partial class WebUserControl : System.Web.UI.UserControl

{

public event EventHandler obj;





public string st

{

get

{

return this.TextBox1.Text;

}



}

protected void Page_Load(object sender, EventArgs e)

{



}

protected void Button1_Click(object sender, EventArgs e)

{

obj(sender, e);

}

}

protected void Page_Load(object sender, EventArgs e)

{

WebUserControl1.obj += new EventHandler(Button1_Click);

}



protected void Button1_Click(object sender, EventArgs e)

{

Label1.Text = WebUserControl1.st;



}