RegisterClientScriptBlock与attribute的区别

  1、private void BtnSend_Click(object sender, System.EventArgs e)
  {
   Page.RegisterClientScriptBlock("Send","<Script Language = javascript> return OnConfirme_ToSend(); </Script>"); 
 }

与

    2、 BtnConfirm.Attributes.Add("onclick","return DialogConfirm();");


2中会生产onclick=" return OnConfirme_ToSend(); " 的语句；用1的RegisterClientScriptBlock表示该]如何表示？