获得触发POSTBACK事件的控件ID(转)

private string getPostBackControlName()
    {
        Control control = null;
        string ctrlname = Page.Request.Params["__EVENTTARGET"];
        if (ctrlname != null && ctrlname != String.Empty)
        {
            control = Page.FindControl(ctrlname);
        }
        else
        {
            Control c;
            foreach (string ctl in Page.Request.Form)
            {
                if (ctl.EndsWith(".x") || ctl.EndsWith(".y"))
                {
                    c = Page.FindControl(ctl.Substring(0, ctl.Length - 2));
                }
                else
                {
                    c = Page.FindControl(ctl);
                }
                if (c is System.Web.UI.WebControls.Button ||
                         c is System.Web.UI.WebControls.ImageButton)
                {
                    control = c;
                    break;
                }
            }
        }
        if (control != null)
            return control.ID;
        else
            return string.Empty;
    }