擷取觸發頁面回調的控制項的方法

    protected void Page_Load(object sender, EventArgs e)
    {

            Control control =  GetPostBackControl(this);
        //if (null != control)
        //{
        //    string controlName = control.ClientID;
        //}
    }

    private Control GetPostBackControl(Page page)
    {
        Control control = null;

        string postBackControlName = Request.Params.Get("__EVENTTARGET");

        string eventArgument = Request.Params.Get("__EVENTARGUMENT");
        if (postBackControlName != null && postBackControlName.Length > 0)
        {
            control = Page.FindControl(postBackControlName);
        }

        else
        {
            foreach (string str in Request.Form)
            {
                Control c = Page.FindControl(str);
                if (c is Button)
                {
                    control = c;
                    break;
                }
            }
        }

        return control;
    }