set timer on key up page load c# .nat

Question

hii,

 i want when i type text then finish the page is post back i will use this code on page load event

 

txtSearch.Attributes.Add("onkeyup", "setTimeout('__doPostBack(\\'" + txtSearch.ClientID.Replace("_", "$") + "\\',\\'\\')', );"); 

 

i want give 10 sec time to  input text in text box