ProxyBoys

Node Js Parse Html

• November 16, 2021
• 0

node-html-parser – npm

Fast HTML Parser is a very fast HTML parser. Which will generate a simplified
DOM tree, with element query support.
Per the design, it intends to parse massive HTML files in lowest price, thus the
performance is the top priority. For this reason, some malformatted HTML may not
be able to parse correctly, but most usual errors are covered (eg. HTML4 style
no closing

‘);
String(); //

var HTMLParser = require(‘node-html-parser’);
var root = (‘

• Hello World

‘);
Global Methods
parse(data[, options])
Parse given data, and return root of the generated DOM.
data, data to parse
options, parse options
{
lowerCaseTagName: false, // convert tag name to lower case (hurt performance heavily)
comment: false, // retrieve comments (hurt performance slightly)
blockTextElements: {
script: true, // keep text content when parsing
noscript: true, // keep text content when parsing
style: true, // keep text content when parsing
pre: true // keep text content when parsing}}
valid(data[, options])
Parse given data, return true if the givent data is valid, and return false if not.
HTMLElement Methods
HTMLElement#trimRight()
Trim element from right (in block) after seeing pattern in a TextNode.
HTMLElement#removeWhitespace()
Remove whitespaces in this sub tree.
HTMLElement#querySelectorAll(selector)
Query CSS selector to find matching nodes.
Note: Full css3 selector supported since v3. 0. 0.
HTMLElement#querySelector(selector)
Query CSS Selector to find matching node.
HTMLElement#getElementsByTagName(tagName)
Get all elements with the specified tagName.
Note: * for all elements.
HTMLElement#closest(selector)
Query closest element by css selector.
HTMLElement#appendChild(node)
Append a child node to childNodes
HTMLElement#insertAdjacentHTML(where, html)
parses the specified text as HTML and inserts the resulting nodes into the DOM tree at a specified position.
HTMLElement#setAttribute(key: string, value: string)
Set value to key attribute.
HTMLElement#setAttributes(attrs: Record)
Set attributes of the element.
HTMLElement#removeAttribute(key: string)
Remove key attribute.
HTMLElement#getAttribute(key: string)
Get key attribute.
HTMLElement#exchangeChild(oldNode: Node, newNode: Node)
Exchanges given child with new child.
HTMLElement#removeChild(node: Node)
Remove child node.
HTMLElement#toString()
Same as outerHTML
HTMLElement#set_content(content: string | Node | Node[])
Set content. Notice: Do not set content of the root node.
HTMLElement#remove()
Remove current element.
HTMLElement#replaceWith(.. (string | Node)[])
Replace current element with other node(s).
HTMLElement#classList
Add class name.
place(old: string, new: string)
Replace class name with another one.
()
Remove class name.
(className: string):void
Toggle class.
ntains(className: string): boolean
Get if contains
get class names
HTMLElement Properties
HTMLElement#text
Get unescaped text value of current node and its children. Like innerText.
(slow for the first time)
HTMLElement#rawText
Get escaped (as-it) text value of current node and its children. May have
& in it. (fast)
HTMLElement#tagName
Get tag name of HTMLElement. Notice: the returned value would be an uppercase string.
HTMLElement#structuredText
Get structured Text
HTMLElement#structure
Get DOM structure
HTMLElement#firstChild
Get first child node
HTMLElement#lastChild
Get last child node
HTMLElement#innerHTML
Set or Get innerHTML.
HTMLElement#outerHTML
Get outerHTML.
HTMLElement#nextSibling
Returns a reference to the next child node of the current element’s parent.
HTMLElement#nextElementSibling
Returns a reference to the next child element of the current element’s parent.
HTMLElement#textContent
Get or Set textContent of current element, more efficient than set_content.
HTMLElement#attributes
Get all attributes of current element. Notice: do not try to change the returned value.
HTMLElement#range
Corresponding source code start and end indexes (ie [ 0, 40])

Web Scraping and Parsing HTML with Node.js and Cheerio

The internet has a wide variety of information for human consumption. But this data is often difficult to access programmatically if it doesn’t come in the form of a dedicated REST API. With tools like Cheerio, you can scrape and parse this data directly from web pages to use for your projects and applications.
Let’s use the example of scraping MIDI data to train a neural network that can generate classic Nintendo-sounding music. In order to do this, we’ll need a set of music from old Nintendo games. Using Cheerio we can scrape this data from the Video Game Music Archive.
Getting started and setting up dependencies
Before moving on, you will need to make sure you have an up to date version of and npm installed.
Navigate to the directory where you want this code to live and run the following command in your terminal to create a package for this project:
The –yes argument runs through all of the prompts that you would otherwise have to fill out or skip. Now we have a for our app.
For making HTTP requests to get data from the web page we will use the Got library, and for parsing through the HTML we’ll use Cheerio.
Run the following command in your terminal to install these libraries:
npm install got@10. 4. 0 cheerio@1. 0. 0-rc. 3
Cheerio implements a subset of core jQuery, making it a familiar tool to use for lots of JavaScript developers. Let’s dive into how to use it.
Using Got to retrieve data to use with Cheerio
First let’s write some code to grab the HTML from the web page, and look at how we can start parsing through it. The following code will send a GET request to the web page we want, and will create a Cheerio object with the HTML from that page. We’ll name it $ following the infamous jQuery convention:
const fs = require(‘fs’);
const cheerio = require(‘cheerio’);
const got = require(‘got’);
const vgmUrl= ”;
got(vgmUrl)(response => {
const $ = ();
($(‘title’)[0]);})(err => {
(err);});
With this $ object, you can navigate through the HTML and retrieve DOM elements for the data you want, in the same way that you can with jQuery. For example, $(‘title’) will get you an array of objects corresponding to every