why some times asp.net button click event(dynamically) was not firing

why some times asp.net button click event(dynamically) was not firing

Hi,

A dynamic click event of asp.net button was working fine for a few days, after that it was not firing what's wrong in that 

<asp:Button ID="btnNames" runat="server" OnClick=" btnNames_Click" CssClass="hidedata" />

Invoke("btnNames");
function Invoke(buttonID){

      $("#"+buttonID).trigger('click');

}

Srihari(:~