javascript - GetElementById interferes with ajaxToolkit:UpdatePanelAnimationExtender and asp:UpdatePanel -

i'm trying call button click using javascript working. code i'm using is:

<script type="text/javascript">         function fncsave() {             document.getelementbyid('<%= savebtn.clientid %>').click();         } </script> 

i'm using updatepanel avoid flickering of page , i'm using ajaxtoolkit add animation updatepanel.

<ajaxtoolkit:updatepanelanimationextender id="anipanel1" runat="server" targetcontrolid="panel1">     <animations>        <onupdated>           <fadein duration="1.0" fps="24"></fadein>        </onupdated>     </animations> </ajaxtoolkit:updatepanelanimationextender> 

my issue here when call button click using javascript updatepanel doesn't work along fadein effect of ajaxtoolkit.

if remove javascript part works fine.

what can here make work? appreciated it.