select drop-down value dynamically create text box c#

Question

hi friend:

 

 

i want to select drop down value create text box like:

 

<asp:DropDownList ID="slct" runat="server">

<asp:listitem Value="1">1</asp:listitem>

<asp:listitem Value="2">2</asp:listitem>

<asp:listitem Value="3">3</asp:listitem>

</asp:DropDownList>

 

select on create on text box

 

and select 2 then create two text box ...