JS创建Tag标签的方法详解

var x = document.createElement("TagName")

x.setAttribute("class",类名)

x.innerHTML = 内容 //赋值

要添加到的元素.appendChild(x);

<div class="container">
    <h3 style="text-align: center">单击下面得"添加"按钮添加标签</h3>
    <div class="dispanel" id="box"></div>
    <button class="btn" id="btn1">全部清除</button>
    <ul id="ul">
      <li><span>John Doe1</span> <button class="clibtn btn">添加</button></li>
      <li><span>John Doe2</span> <button class="clibtn btn">添加</button></li>
      <li><span>John Doe3</span> <button class="clibtn btn">添加</button></li>
      <li><span>John Doe4</span> <button class="clibtn btn">添加</button></li>
      <li><span>John Doe5</span> <button class="clibtn btn">添加</button></li>
      <li><span>John Doe6 </span><button class="clibtn btn">添加</button></li>
    </ul>
</div>

body{
  margin:0 ;
  padding:0;
  background-color:#002F4F;
  color: #ffffff;
  font-family: "微软雅黑";
  font-size: 1em;
}
ul,h3{margin: 0;
  list-style: none;
padding: 0px}
.container{
  width:300px;
  height:350px;
  margin: 50px auto;
}
.dispanel{
  width: 290px;
  height:50px;
  background-color: #ffffff;
  margin: 0 auto;
}
.btn{
  width:100px;
  height:20px;
  color: #ffffff;
  background-color:red;
  border: 0px;
  font-size: 1em;
  margin:10px 0 10px 5px;
}
.container ul li{
  width:300px;
  height:30px;
  margin-top:10px;
}
.spanstyle{display: inline-block;
  color:#000;
  width:85px;height:22px;
  background-color: bisque;
  margin-left:5px;
  font-size: 12px;
  text-align: center;
  line-height: 22px;
}

var oUl = document.getElementById("ul");
var oBtn = oUl.getElementsByClassName("btn");
var oLi = document.getElementsByClassName("li");
var oBox = document.getElementById("box");
for(var i = 0;i<oBtn.length;i++) {
    oBtn[i].onclick = function () {
      var oA = document.createElement("span");  //创建一个节点Node
      var oNew = oA.setAttribute("class", "spanstyle"); //将节点上增加class样式
      var ospan = this.previousElementSibling.innerHTML + " X"; //this == oBtn[i] / previousElementSiling:上一个元素的兄弟节点 即 <span>
      oA.innerHTML = ospan; //将ospa的值付给新创建的节点Node oA.
      oBox.appendChild(oA); //将oA 添加为oBox的儿子
      oA.onclick=function () {
        oBox.removeChild(oA); //移除这个元素
      }
    }
}
var obtn1 = document.getElementById("btn1");
obtn1.onclick=function () {
    oBox.innerHTML=""; //清除内容
}