Home > Article > Web Front-end > Node operation examples in JS

Node operation examples in JS

小云云Original: 2018-03-26 16:16:411333browse

This article mainly shares with you examples of node operations in JS, mainly in the form of code, hoping to help everyone.

Node addition, deletion and modification query

<!DOCTYPE html><html lang="en"><head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .p1,.p2,.p3,.p4{            width: 300px;            height: 100px;        }
        .p1{            background-color: green;        }
         .p2{            background-color: yellow;        }
         .p3{            background-color: rebeccapurple;        }
         .p4{            background-color: deeppink;        }
    </style></head><body><p class="p1">
    <button onclick="add()">add</button>
    hello p1</p><p class="p2">
    <button onclick="del()">del</button>
    hello p2</p><p class="p3">
    <button onclick="change()">change</button>
    <p>hello p3</p></p><p class="p4">hello p4</p><script>###############增加节点######################    function change() {
        var img=document.createElement("img");//<img src="">
        //img.setAttribute("src","meinv.jpg");
        img.src="meinv.jpg";        var ele=document.getElementsByTagName("p")[0];        var father=document.getElementsByClassName("p3")[0];

        father.replaceChild(img,ele)


    }
    ###############修改节点######################    function add() {
        var ele=document.createElement("p");//<p></p>
        ele.innerHTML="<h1>hello p</h1>";        //ele.innerText="<h1>hello p</h1>";
        ele.style.color="red";
        ele.style.fontSize="10px";        var father=document.getElementsByClassName("p1")[0];
        father.appendChild(ele)

    }
###############删除节点######################    function del() {
        var father=document.getElementsByClassName("p1")[0];        var son=father.getElementsByTagName("p")[0];
        father.removeChild(son)
    }</script></body></html>

Two ways to use JS to bind events

<!DOCTYPE html><html lang="en"><head>
    <meta charset="UTF-8">
    <title>Title</title></head><body><p onclick="func(this)">hello</p><p>hello p</p><script>
    // 绑定事件方式一
    function func(self) {
        console.log(self)
        alert(1234)
    }    // 绑定事件方式二
    var ele=document.getElementsByTagName("p")[0]
    ele.onclick=function () {
        console.log(ele);
        console.log(this);//        alert(6666)


    }</script></body></html>

JS class attribute

<script>
    var ele=document.getElementsByTagName("p")[0];
      # class的名称
    console.log(ele.className);
          # 以列表返回class中值
    console.log(ele.classList[0]);
          # 以列表返回class中值
    console.log(ele.classList[1]);
    #  向列表中增加元素
    ele.classList.add("hide")
    console.log(ele.className);</script>

Event object: encapsulated Event information
can be used to prevent event propagation

<!DOCTYPE html><html lang="en"><head>
    <meta charset="UTF-8">
    <title>Title</title></head><body><form action="" id="form1">
    <input type="text" name="username">
    <input type="submit" value="提交"></form><script>
    var ele=document.getElementById("form1");
    ele.onsubmit=function (e) {//        console.log("hello")
        alert(1234);        // 方式一  返回false
         return false
        // 方式二  preventDefault函数
        //e.preventDefault()
    }</script></body></html>

Related recommendations:

Summary of native JavaScript operations on dom nodes

The above is the detailed content of Node operation examples in JS. For more information, please follow other related articles on the PHP Chinese website!

JavaScript 封装 class Event JS 对象事件 dom

Statement：

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Previous article：JS code to achieve automatic typing effectNext article：JS code to achieve automatic typing effect

See more

Node operation examples in JS

Related articles