I want to Bind Dropdownlist from another dropdown without postback

<script type="text/javascript">
       function populateDD2() {
           var dd1 = document.getElementById('<%=DD1.ClientID %>');
           var dd2 = document.getElementById('<%=DD2.ClientID %>');
           if (dd1.value == "Yes") {
               var options = ["Option 1", "Option 2", "Option 3"];
               for (var i = 0; i < options.length; i++) {
                   var opt = document.createElement("option");
                   opt.value = i;
                   opt.innerHTML = options[i];
                   dd2.appendChild(opt);
               }
           }
           else {
               dd2.options = null;// Or whatever else you might want to do.
           }
       }
   </script>

<asp:DropDownList runat="server" ID="DD1" onchange="populateDD2()">
            <asp:ListItem Text="- Select -"></asp:ListItem>
            <asp:ListItem Text="Yes"></asp:ListItem>
            <asp:ListItem Text="No"></asp:ListItem>
        </asp:DropDownList>
        <asp:DropDownList runat="server" ID="DD2">
        </asp:DropDownList>