jstl标签库(3)

jstl标签库(3)

jstl函数库(fn)

Action

package  com.lanjh.struts.action;

import  java.util.ArrayList;
import  java.util.List;

import  javax.servlet.http.HttpServletRequest;
import  javax.servlet.http.HttpServletResponse;

import  org.apache.struts.action.Action;
import  org.apache.struts.action.ActionForm;
import  org.apache.struts.action.ActionForward;
import  org.apache.struts.action.ActionMapping;

/**
 * 测试jstl函数库
 *  @author  Administrator
 *
  */
public   class  JstlFnAction  extends  Action {

    @Override
     public  ActionForward execute(ActionMapping mapping, ActionForm form,
            HttpServletRequest request, HttpServletResponse response)
             throws  Exception {
        
        request.setAttribute( " hello " ,  " hello world " );
        
        List list  =   new  ArrayList();
        list.add( " t1 " );
        list.add( " t2 " );
        
        request.setAttribute( " list " , list);
        
        request.setAttribute( " name " ,  " Tom " );
         return  mapping.findForward( " success " );
    }

}

struts配置

< action  path ="/jstlfn"
            type ="com.lanjh.struts.action.JstlFnAction" >
             < forward  name ="success"  path ="/jstl_fn.jsp" ></ forward >
         </ action >

JSP页面

<% @ page language = " java "  contentType = " text/html; charset=utf-8 "
    pageEncoding = " GB18030 " %>
<% @ taglib prefix = " fn "  uri = " http://java.sun.com/jsp/jstl/functions " %>    

<! DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd" >
< html >
< head >
< meta  http-equiv ="Content-Type"  content ="text/html; charset=GB18030" >
< title > 测试jstl函数库 </ title >
</ head >
< body >
     < h1 > 测试jstl函数库 </ h1 >
     < hr >
    hello.length=(jsp脚本): <% = (( String )request.getAttribute( " hello " )).length()  %> < br >
     <!--   hello.length(jstl函数库，函数调用必须在el表达式中 前缀+冒号+函数名):${fn:length(hello) }  -->
    hello.length(jstl函数库，函数调用必须在el表达式中 前缀+冒号+函数名):${fn:length(hello) } < br >
    list.length:${fn:length(list) } < br >

</ body >
</ html >