Traverse (preferably to a specific array of target values) and the JSTL EL expressions for to achieve the dual loop

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                     JSTL and EL expressions for implementation of the Java double loop

 

1, the introduction of two jstl tag library in jsp page

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

2, Maven project to add jar package dependencies, packages and standard packages need jstl

		<!-- https://mvnrepository.com/artifact/taglibs/standard -->
		<dependency>
		    <groupId>taglibs</groupId>
		    <artifactId>standard</artifactId>
		    <version>1.1.2</version>
		</dependency>
		<!-- https://mvnrepository.com/artifact/javax.servlet/jstl -->
		<dependency>
		    <groupId>javax.servlet</groupId>
		    <artifactId>jstl</artifactId>
		    <version>1.2</version>
		</dependency>

3, in a custom array jsp

	<% 
		String[][] str3 = {{"李白1","杜甫1","白居易1"},{"李白2","杜甫2","白居易2"},{"李白3","杜甫3","白居易3"}}; 
		application.setAttribute("str3", str3);
	%>

4, a dual <c: foreach> tag iterate

	<c:forEach var="i" begin="0" end="${fn:length(array)-1 }">
		<c:forEach var="j" begin="0" end="${fn:length(array[i])-1 }">
			${array[i][j] }
		</c:forEach>
	</c:forEach>

Screenshot results:

5, fn labels do not need to traverse the List

	<%
		List<String> list = new ArrayList<String>();
		list.add("功夫大师");
		list.add("圆明园");
		list.add("景福宫");
		request.setAttribute("list", list);
	%>

Screenshot results: