使用struts Logic taglib生成选择选项

Question

Is it possible to display Select box with options filled with numbers as below in struts by using struts Logic taglib.

<select>
 <option value="20">20</option>
 <option value="21">21</option>
 <option value="22">22</option>
 <option value="23">23</option>
 <option value="24">24</option>
 <option value="25">25</option>
</select>

Some thing like one below

<logic:iterate start="20" end="25" id="Num">
  <option value="Num">Num</option>
</logic:iterate>

Answer 1

Struts' logic iterate tag is meant to iterate over a collection :

Repeats the nested body content of this tag once for every element of the specified collection, which must be an Iterator, a Collection, a Map (whose values are to be iterated over), or an array.

Source : logic iterate definition

If the only purpose is to generate a simple select with the index as value for options, use JSTL instead :

<select>
    <c:forEach begin="20" end="25" varStatus="loop">
        <option value="${loop.index}">${loop.index}</option>    
    </c:forEach>
</select>

It is not a problem to use JSTL rather than struts tags :

The Struts team encourages the use of the standard tags over the Struts specific tags when possible.

Don't forget to import the JSTL core taglib :

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>

Answer 2

In struts 2, select tag is used to display the dropdown and it takes a collection as input. More info on this can be found at

apache official page for select tag

and a good tutorial on select tag