How to find which control has caused the postback on the page

I need to find the control which has caused the postback on my page. I am working in c# please help me.

kevin said:

I need to find the control which has caused the postback on my page. I am working in c# please help me.

Hi Kevin,

 Try the following code:

protected void Page_Load(object sender, EventArgs e)
        {
         //on every postback you can print the ID of the control which caused postback
            if (IsPostBack)
            {
                Control ctl = GetPostBackControl(Page);
                if (ctl != null)
                    Response.Write(ctl.ID);
            }
        }

//method that Identify the postback control
public static Control GetPostBackControl(System.Web.UI.Page page)
        {
            Control control = null;
            string ctrlname = page.Request.Params["__EVENTTARGET"];
            if (ctrlname != null && ctrlname != String.Empty)
            {
                control = page.FindControl(ctrlname);
            }
            // if __EVENTTARGET is null, the control is a button type and we need to 
            // iterate over the form collection to find it
            else
            {
                string ctrlStr = String.Empty;
                Control c = null;
                foreach (string ctl in page.Request.Form)
                {
                    // handle ImageButton controls ...
                    if (ctl.EndsWith(".x") || ctl.EndsWith(".y"))
                    {
                        ctrlStr = ctl.Substring(0, ctl.Length - 2);
                        c = page.FindControl(ctrlStr);
                    }
                    else
                    {
                        c = page.FindControl(ctl);
                    }
                    if (c is System.Web.UI.WebControls.Button ||
                             c is System.Web.UI.WebControls.ImageButton)
                    {
                        control = c;
                        break;
                    }
                }
            }
            return control;
        }

let me know if its not working..

Simply stick to string controlID = Request.Params["__EVENTTARGET"]; as you don't know whether it is Button, ImageButton , LinkButton, DropDown or else.. which has caused the postback.