jsp中的el表达式和小脚本

小灰灰 2023-07-17 07:08 21阅读 0赞

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<%@ page language="java" contentType="text/html; charset=utf-8"
 pageEncoding="utf-8" isELIgnored="false"%>
  
 <%
 	request.setAttribute("hometown", "江西省赣州市于都县");
 	//故意取一个带中划线的名字(特殊的名字)
 	session.setAttribute("test-hobby", "爬山");
 	application.setAttribute("age", 6);
 %> 
 <!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=utf-8">
 <title>EL表达式</title>
 </head>
 <body>
 <h1>EL表达式</h1>
 ${5 + 6 } 
 ${hometown} 
 ${age} 
 <%-- 
 ${test-hobby}这种写法会报错
 ${["test-hobby"]}这种写法也会报错
 ${['test-hobby']}这种写法也会报错
 --%>
 ${sessionScope["test-hobby"]}这种写法正常执行 
 ${sessionScope['test-hobby']}这种写法正常执行 
 ${city}故意写一个不存在的city属性名 
 ${true} 
 ${false} 
 ${5 > 2} 
 ${'a'} 
 ${'abc'} 
 ${"江西省"} 
 ${"于都县"} 
 想在网页上原原本本的显示出${}
 <%
 	String[] names = {"苏荃", "双儿", "阿珂", "建宁公主", "沐剑屏", "方怡", "曾柔"};
 	request.setAttribute("names", names);
 %>
 
 <%
 	int test = 66;
 %>
 ${names[0]} 
 ${names[1]} 
 ${names[2]} 
 <%
 	int count = names.length;
 	for(int index = 0; index < count; index++){
 %>
 	${names[index]} 获取不到index,但是也不会报错 
 <%
 	}
 %>
 
 <%=count %>
 <hr>
 <%
 	out.print(test);
 %>
 <hr>
 <%
 	int i = 0;
 	for(; i < 5; i++){
 		out.print(i + " ");	
 	}
 %>
 <hr>
 <%
 	for(int k = 20; k < 25; k++){
 		out.print(k);
 %>
 
 <%
 	}
 %>
 <hr>
 <%
 	for(int x = 60; x < 65; x++){
 		out.println(x);
 	}
 	for(int x = 90; x < 95; x++){
 		out.print(x);
 	}
 %>
 <hr>
 </body>
 </html>

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[20200320150452336.png]: /images/20230528/304e9d98b33d4ecc8660722740e80c21.png
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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2N6aDUwMA_size_16_color_FFFFFF_t_70 4]: /images/20230528/b11dc4b8b3d546b59f3bc3563eef7bc3.png