留言条.html .js来完成

let data = [{   username: "张桑0",   time: "2017-09-07 12:00:00",   text: "留言文本内容。"},{   username: "张桑1",   time: "2017-09-08 12:00:00",   text: "留言文本内容。"},{   username: "张桑2",   time: "2017-09-09 12:00:00",   text: "留言文本内容。"}];

render();addBtn.addEventListener("click", () => {   addMessage();}, false)

content.addEventListener("keydown", (e) => {   if(e.keyCode === 13){      addMessage();   }}, false)

exhibit.addEventListener("click", (e) => {   if(e.target.className === "removeBtn"){      e.preventDefault();      let i = e.target.getAttribute("_id");      data.splice(i, 1);   }   render();}, false)

function render(){   exhibit.innerHTML = data.map((item, index) => {      return `<div class="message">               <div class="info">                  <span>${item.username}</span>                  <span>${item.time}</span>               </div>               <p>${item.text}</p>               <div class="btn">                  <a href="#" class="removeBtn" _id="${index}">删除</a>               </div>            </div>`   }).join("");}

function addMessage(){   data.push({      username: `张三${data.length}`,      time: getNowTime(),      text: content.value   });   content.value = "";   render();}

function getNowTime(){   let date = new Date();   let year = date.getFullYear();   let month = date.getMonth() + 1;

month = judgeTime(month);

let day = date.getDate();   let hours = date.getHours();   let minutes = date.getMinutes();   let seconds = date.getSeconds();

let nowTime = `${year}-${month}-${day} ${hours}:${minutes}:${seconds}`;   return nowTime;}

function judgeTime(time){   if(time < 10 && time > 0){      time = "0" + time;   }   return time;}