This article will introduce to youjs about the acquisition of Dom's childNodes and childrens and related nodes. It has certain reference value. Friends in need can refer to it. I hope it will be helpful to you.
DOM-Document Object Model
Node Type
Each DOM node has a nodeType attribute to represent the type of the node. There are 12 types in total, the common ones are ELEMENT_NODE=1;ATTRIBUTE_NODE=2;TEXT_NODE=3
Example
<p>
p
</p><p>
doughter
</p>
<p>
son
</p>
<p>
cousin
</p>
Copy after login
For the p node, nodeType=1, nodeName="p" nodeValue =null
(nodeName saves the tag name)
var p = document.getElementById("p")
Copy after login
The attributes of node in P
##There is also a childNodes in P Properties, which are stored in the NodeList object. NodeList is an array-like object used to save an ordered set of
nodes, which can be accessed by location. Although the value of NodeList can be accessed through square bracket syntax, and this object also has a length property, it is not an instance of Array. The unique point of the NodeList object is that it is actually the result of dynamically executing a query based on the DOM structure, so changes in the DOM structure can be automatically reflected in the NodeList.
There is also an attribute called childrens for nodes. According to "Javascript Advanced Programming": Due to differences between other versions before IE9 and other browsers in handling whitespace characters in text nodes, the children attribute has appeared for a long time. This attribute is an instance of HTMLCollection and only contains child nodes
that are also elements in the element. Other than that, there is no difference between the two.
Based on the above example, let’s output both the childNodes and children of pp.children
p.childNodes
It can be seen that1. The two belong to different instances, children is an instance of HTMLCollection, and childNodes is an instance of childNodes2 . children only contains child nodes that are also elements, and childNodes returns a collection of child elements of the element, including HTML nodes, attribute nodes, and text nodes. You can use nodeType to determine what type of node it is. It is an element node only when nodeType==1. (2=attribute node, 3=text node)The support for childNodes is as follows
IE6-8/Safari/Chrome/Opera
IE9/Firefox
##childNodes(i)
Supported
Not supported
可以通过一下方法进行转化
var arr = Array.prototype.slice.call(p.childNodes,0);
arr.filter((item,index)=>(
item.nodeType===1
))
The above is the detailed content of js about the acquisition of Dom's childNodes and childrens and related nodes. For more information, please follow other related articles on the PHP Chinese website!
Statement of this Website
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
How to use JS and Baidu Map to implement map pan function Baidu Map is a widely used map service platform, which is often used in web development to display geographical information, positioning and other functions. This article will introduce how to use JS and Baidu Map API to implement the map pan function, and provide specific code examples. 1. Preparation Before using Baidu Map API, you first need to apply for a developer account on Baidu Map Open Platform (http://lbsyun.baidu.com/) and create an application. Creation completed
Face detection and recognition technology is already a relatively mature and widely used technology. Currently, the most widely used Internet application language is JS. Implementing face detection and recognition on the Web front-end has advantages and disadvantages compared to back-end face recognition. Advantages include reducing network interaction and real-time recognition, which greatly shortens user waiting time and improves user experience; disadvantages include: being limited by model size, the accuracy is also limited. How to use js to implement face detection on the web? In order to implement face recognition on the Web, you need to be familiar with related programming languages and technologies, such as JavaScript, HTML, CSS, WebRTC, etc. At the same time, you also need to master relevant computer vision and artificial intelligence technologies. It is worth noting that due to the design of the Web side
Essential tools for stock analysis: Learn the steps to draw candle charts in PHP and JS. Specific code examples are required. With the rapid development of the Internet and technology, stock trading has become one of the important ways for many investors. Stock analysis is an important part of investor decision-making, and candle charts are widely used in technical analysis. Learning how to draw candle charts using PHP and JS will provide investors with more intuitive information to help them make better decisions. A candlestick chart is a technical chart that displays stock prices in the form of candlesticks. It shows the stock price
How to use PHP and JS to create a stock candle chart. A stock candle chart is a common technical analysis graphic in the stock market. It helps investors understand stocks more intuitively by drawing data such as the opening price, closing price, highest price and lowest price of the stock. price fluctuations. This article will teach you how to create stock candle charts using PHP and JS, with specific code examples. 1. Preparation Before starting, we need to prepare the following environment: 1. A server running PHP 2. A browser that supports HTML5 and Canvas 3
How to use JS and Baidu Maps to implement the map heat map function Introduction: With the rapid development of the Internet and mobile devices, maps have become a common application scenario. As a visual display method, heat maps can help us understand the distribution of data more intuitively. This article will introduce how to use JS and Baidu Map API to implement the map heat map function, and provide specific code examples. Preparation work: Before starting, you need to prepare the following items: a Baidu developer account, create an application, and obtain the corresponding AP
Overview of how to use JS and Baidu Maps to implement map click event processing: In web development, it is often necessary to use map functions to display geographical location and geographical information. Click event processing on the map is a commonly used and important part of the map function. This article will introduce how to use JS and Baidu Map API to implement the click event processing function of the map, and give specific code examples. Steps: Import the API file of Baidu Map. First, import the file of Baidu Map API in the HTML file. This can be achieved through the following code:
With the rapid development of Internet finance, stock investment has become the choice of more and more people. In stock trading, candle charts are a commonly used technical analysis method. It can show the changing trend of stock prices and help investors make more accurate decisions. This article will introduce the development skills of PHP and JS, lead readers to understand how to draw stock candle charts, and provide specific code examples. 1. Understanding Stock Candle Charts Before introducing how to draw stock candle charts, we first need to understand what a candle chart is. Candlestick charts were developed by the Japanese
How to use JS and Baidu Maps to implement map polygon drawing function. In modern web development, map applications have become one of the common functions. Drawing polygons on the map can help us mark specific areas for users to view and analyze. This article will introduce how to use JS and Baidu Map API to implement map polygon drawing function, and provide specific code examples. First, we need to introduce Baidu Map API. You can use the following code to import the JavaScript of Baidu Map API in an HTML file
Web Front-end
