本文实例为大家分享了JavaWeb开发实现备忘录的具体代码，供大家参考，具体内容如下
(资料图片)
所用技术
HTML，CSS，JavaScript，Servlet，Tomcat 8.5.60，Mysql 5.7
数据库表
开发工具
IDEA，MySQL Workbench
功能
1、添加未完成事项
2、完成事项
项目演示截图
前端设计
<!DOCTYPE html><html lang="en" ><head> <meta charset="UTF-8"> <title>To-Do-List设计</title> <link rel="stylesheet" href="./style.css" ></head><body><section class="container"> <div class="heading"> <img class="heading_img" src="girl.svg"> <h1 class="heading_title">To-Do List</h1> </div> <form class="form"> <div> <label class="form_label" for="todo">~ Today I want to do ~</label> <input class="form_input" type="text" id="todo" name="to-do" size="30" required> <button class="button" type="type"><span>Submit</span></button> </div> </form> <div> <ul class="toDoList"></ul> </div></section><!-- partial --> <script src="./script.js"></script></body></html>
body { background-color: #f7d3c1; min-height: 70vh; padding: 1rem; box-sizing: border-box; display: flex; justify-content: center; align-items: center; color: #494a4b; font-family: "Gochi Hand", cursive; text-align: center; font-size: 130%;}@media only screen and (min-width: 500px) { body { min-height: 100vh; }}.container { width: 100%; height: auto; min-height: 500px; max-width: 500px; min-width: 250px; background: #f1f5f8; background-image: radial-gradient(#bfc0c1 7.2%, transparent 0); background-size: 25px 25px; border-radius: 20px; box-shadow: 4px 3px 7px 2px #000000; padding: 1rem; box-sizing: border-box;}.heading { display: flex; align-items: center; justify-content: center; margin-bottom: 1rem;}.heading_title { transform: rotate(2deg); padding: 0.2rem 1.2rem; border-radius: 20% 5% 20% 5%/5% 20% 25% 20%; background-color: lightpink; font-size: 1.5rem;}@media only screen and (min-width: 500px) { .heading_title { font-size: 2rem; }}.heading_img { width: 24%;}.form_label { display: block; margin-bottom: 0.5rem;}.form_input { box-sizing: border-box; background-color: transparent; padding: 0.7rem; border-bottom-right-radius: 15px 3px; border-bottom-left-radius: 3px 15px; border: solid 3px transparent; border-bottom: dashed 3px #95a9ea; font-family: "Gochi Hand", cursive; font-size: 1rem; color: rgba(63, 62, 65, 0.7); width: 70%; margin-bottom: 20px;}.form_input:focus { outline: none; border: solid 3px #95a9ea;}@media only screen and (min-width: 500px) { .form_input { width: 60%; }}.button { padding: 0; border: none; transform: rotate(4deg); transform-origin: center; font-family: "Gochi Hand", cursive; text-decoration: none; padding-bottom: 3px; border-radius: 5px; box-shadow: 0 2px 0 #494a4b; transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275); background-image: url("data:image/gif;base64,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"); background-color: rgba(0, 119, 255, 0.7);}.button span { background: #f1f5f8; display: block; padding: 0.5rem 1rem; border-radius: 5px; border: 2px solid #494a4b;}.button:active, .button:focus { transform: translateY(4px); padding-bottom: 0px; outline: 0;}.toDoList { text-align: left;}.toDoList li { position: relative; padding: 0.5rem;}.finish{ text-decoration: line-through wavy #fb8524b6;}.toDoList li:hover { text-decoration: line-through wavy #fb8524b6;}var htmlRoot = document.querySelector("html");var ulTodoList = document.querySelector("ul.toDoList");var input = document.querySelector("input#todo");function finishTodoItem() { //this 就是触发事件的元素（就是用户点击的元素） var id = this.dataset.id; var url = "/finish?id=" + id; var xhr = new XMLHttpRequest(); var self = this; xhr.open("get",url); xhr.send(); xhr.onload = function () { self.classList.add("finish"); self.onclick = null; }}function appendTodo(todo) { var todoLi = document.createElement("li"); todoLi.innerText = todo.todo; if(todo.state == true){ todoLi.classList.add("finish"); }else{ todoLi.onclick = finishTodoItem; todoLi.dataset.id = todo.id; } ulTodoList.appendChild(todoLi);}//为"submit"按钮绑定save函数function save() { var todoInput = input.value; var url = "/save?todo=" + encodeURI(todoInput); var xhr = new XMLHttpRequest(); function success() { var todo = { "id":parseInt(xhr.responseText), "todo":todoInput, "state":0, }; appendTodo(todo); } xhr.onload = success; xhr.open("get",url); xhr.send();}var submitBtn = document.querySelector(".button");submitBtn.onclick = save;//页面加载完成之后，请求列表资源function LoadTodoList() { var xhr = new XMLHttpRequest(); function success() { if (xhr.status != 200){ htmlRoot.innerHTML = xhr.responseText; return; } //1、JS进行JSON的反序列化 var todoList = JSON.parse(xhr.responseText); //遍历每一项，添加到DOM树中 for (var todo of todoList){ appendTodo(todo); } } xhr.onload = success; xhr.open("get","/list"); xhr.send();}LoadTodoList();后端设计
@WebServlet("/finish")public class FinishServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { //1、获取用户点击事项的id req.setCharacterEncoding("utf-8"); String id = req.getParameter("id"); //进行数据库表的更新 try (Connection c = DBUtil.connection()) { String sql = "UPDATE item set state = 1 WHERE id=?"; try (PreparedStatement s = c.prepareStatement(sql)) { s.setString(1, id); s.executeUpdate(); } } catch (SQLException exc) { throw new ServletException(exc); } }}@WebServlet("/list")public class ListServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { //1、从数据库中查出List<待办事项>todolist List<TodoItem> todolist = new ArrayList<>(); try (Connection c = DBUtil.connection()){ String sql = "SELECT id,todo,state FROM item ORDER BY id"; try(PreparedStatement s = c.prepareStatement(sql)){ try (ResultSet rs = s.executeQuery()){ while(rs.next()){ TodoItem todo = new TodoItem(); todo.id = rs.getInt("id"); todo.todo = rs.getString("todo"); todo.state = rs.getBoolean("state"); todolist.add(todo); } } } } catch (SQLException exc) { throw new ServletException(exc); } //2、把todolist序列化成JSON格式的字符串 ObjectMapper objectMapper = new ObjectMapper(); String s = objectMapper.writeValueAsString(todolist); //3、进行响应输出 resp.setCharacterEncoding("utf-8"); resp.setContentType("application/json"); resp.getWriter().println(s); }}@WebServlet("/save")public class SaveServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { //1、读取用户填写的内容 req.setCharacterEncoding("utf-8"); String todo = req.getParameter("todo"); //2、执行SQL,把内容写入表中 int id; try (Connection c = DBUtil.connection()){ String sql = "INSERT INTO item(todo)VALUES(?)"; try (PreparedStatement s = c.prepareStatement(sql,Statement.RETURN_GENERATED_KEYS)){ s.setString(1,todo); s.executeUpdate(); try(ResultSet rs = s.getGeneratedKeys()){ rs.next(); id = rs.getInt(1); } } } catch (SQLException exc) { throw new ServletException(exc); } //3、手动写一个JSON成功 resp.setCharacterEncoding("utf-8"); resp.setContentType("application/json"); resp.getWriter().println(id); }}public class TodoItem { public Integer id; public String todo; public boolean state;}以上就是本文的全部内容，希望对大家的学习有所帮助，。
关键词： JavaWeb
