关于$(this).attr("value");

package com.imooc.ajax;

public class Song {
	private String name;

	public Song() {

	}

	public Song(String name) {
		super();
		this.name = name;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

}

package com.imooc.ajax;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.alibaba.fastjson.JSON;

/**
 * Servlet implementation class Text2
 */
@WebServlet("/text2")
public class Text2 extends HttpServlet {
	private static final long serialVersionUID = 1L;

	/**
	 * @see HttpServlet#HttpServlet()
	 */
	public Text2() {
		super();
		// TODO Auto-generated constructor stub
	}

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
	 *      response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		List<Song> list = new ArrayList<Song>();
		String type = request.getParameter("name");
		if (type != null && type.equals("流行歌曲")) {
			list.add(new Song("稻香"));
			list.add(new Song("晴天"));
			list.add(new Song("告白气球"));
		} else if (type != null && type.equals("经典歌曲")) {
			list.add(new Song("千千阙歌"));
			list.add(new Song("傻女"));
			list.add(new Song("七友"));
		} else if (type != null && type.equals("摇滚歌曲")) {
			list.add(new Song("一块红布"));
			list.add(new Song("假行僧"));
			list.add(new Song("新长征路上的摇滚"));
		} else {
			System.out.println("error");
		}
		String json = JSON.toJSONString(list);
		System.out.println(json);
		response.setContentType("text/html;charset=utf-8");
		response.getWriter().println(json);
	}

}

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
	<input type="button" id="1" value="流行歌曲">
	<input type="button" id="2" value="经典歌曲">
	<input type="button" id="3" value="摇滚歌曲">
	<div style="text-align: center" id="show"></div>
	<script type="text/javascript" src="js/jquery-3.3.1.js"></script>
	<script type="text/javascript">
		$(function() {
			$("input").click(function() {
				var name = $(this).attr("value");
				$("#show").empty();
				$.ajax({
					"url" : "/ajax/text2",
					"type" : "get",
					"data" : {"name" : name},
					"dataType" : "json",
					"success" : function(json) {
						for (var i = 0; i < json.length; i++) {
							$("#show").append("<h1>" + json[i].name + "</h1>");
						}
					}
				})
			})
		})
	</script>
</body>
</html>