jquery code
$(function() {
$ ("#DropDownList1").bind("change", function() {
$("#Label1").text($("#DropDownList1 option:selected").text());
});
or
$("#DropDownList1").bind("change", function() {
$("#Label1").text($("#DropDownList1").val());
});
Explanation of this:
var name = $("#DropDownList1 option:selected").val(); //Get the selected value in dropdownlist
var name1 = $("#DropDownList1").text(); //Get the value used in dropdownlist