$(document).ready(function () {
$('#<%= btnLeft.ClientID %>').click(function () {
$("#divblock").animate({"left":"-=50px"},"slow");
});
$('#<%= btnRight.ClientID %>').click(function () {
$("#divblock").animate({"left":"+=50px"},"slow");
});
});
Check this out it tested on my side....m sure it will work 100%..!