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最新推荐文章于 2023-06-25 23:32:20 发布

feier7501

最新推荐文章于 2023-06-25 23:32:20 发布

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分类专栏： jsp

本文链接：https://blog.youkuaiyun.com/feier7501/article/details/25001743

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新疆web工程：

Java代码：

package com.tld.bean;

public class UserInfo {
	private String username;
	
	private int age;

	public String getUsername() {
		return username;
	}

	public void setUsername(String username) {
		this.username = username;
	}

	public int getAge() {
		return age;
	}

	public void setAge(int age) {
		this.age = age;
	}
}

tag要继承TagSupport类

package com.tld;

import java.io.IOException;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.TagSupport;

import com.tld.bean.UserInfo;

public class UserInfoTag extends TagSupport {

	private static final long serialVersionUID = 1L;

	private UserInfo user;

	@Override
	public int doEndTag() throws JspException {
		return EVAL_PAGE;
	}

	@Override
	public int doStartTag() throws JspException {
		try {
			JspWriter out = pageContext.getOut();
			if (user == null) {
				out.println("No UserInfo Found...");
				return SKIP_BODY;
			}
			out.println("<div>");
			out.println(user.getUsername());
			out.println("  ");
			out.println(user.getAge());
			out.println("</div>");
		} catch (IOException e) {
			throw new JspException(e.getMessage());
		}

		return SKIP_BODY;
	}

	@Override
	public void release() {
		super.release();
		user = null;
	}

	public UserInfo getUser() {
		return user;
	}

	public void setUser(UserInfo user) {
		this.user = user;
	}
}

编写tld文件，文件名随便取。

UserInfo.tld：

<?xml version="1.0" encoding="UTF-8"?>
<taglib version="2.0" xmlns="http://java.sun.com/xml/ns/j2ee"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee web-jsptaglibrary_2_0.xsd">
	<tlib-version>1.0</tlib-version>
	<jsp-version>2.0</jsp-version>
	<short-name>cc</short-name>
	<uri>/UserInfo</uri>
	<tag>
		<name>showUserInfo</name>
		<tag-class>com.tld.UserInfoTag</tag-class>
		<body-content>empty</body-content>
		<attribute>
			<name>user</name>
			<required>false</required>
			<rtexprvalue>true</rtexprvalue>
		</attribute>
	</tag>
</taglib>

在web.xml里进行配置：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns="http://java.sun.com/xml/ns/javaee" xmlns:jsp="http://java.sun.com/xml/ns/javaee/jsp"
	xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
	xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
	id="WebApp_ID" version="2.5">
	<display-name>tld</display-name>
	<jsp-config>
		<taglib>
			<taglib-uri>/UserInfo</taglib-uri>
			<taglib-location>/WEB-INF/UserInfo.tld</taglib-location>
		</taglib>
	</jsp-config>
	<welcome-file-list>
		<welcome-file>index.html</welcome-file>
		<welcome-file>index.htm</welcome-file>
		<welcome-file>index.jsp</welcome-file>
		<welcome-file>default.html</welcome-file>
		<welcome-file>default.htm</welcome-file>
		<welcome-file>default.jsp</welcome-file>
	</welcome-file-list>
</web-app>

jsp里进行引用：

<%@ page language="java" contentType="text/html; charset=GB18030"
    pageEncoding="GB18030"%>
<%@ taglib uri="/UserInfo" prefix="ui" %>
<%@ page import="com.tld.bean.UserInfo;" %>
<!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>Insert title here</title>
</head>
<body>
<%
UserInfo userInfo = new UserInfo();
userInfo.setUsername("yang");
userInfo.setAge(18);
pageContext.setAttribute("user", userInfo);
%>
<ui:showUserInfo user="${pageScope.user }"/>
</body>
</html>

这样就可以了。

参考：http://www.cnblogs.com/zhaoyang/archive/2011/12/25/2301108.html