Npm Cherio

cheerio – npm

Fast, flexible & lean implementation of core jQuery designed specifically for the server.
中文文档 (Chinese Readme)
const cheerio = require(‘cheerio’);
const $ = (‘

Hello world

‘);
$(”)(‘Hello there! ‘);
$(‘h2’). addClass(‘welcome’);
$();
//=>

Hello there!


Note
We are currently working on the 1. 0. 0 release of cheerio on the main branch. The source code for the last published version, 0. 22. 0, can be found here.
Installation
npm install cheerio
Features
❤ Familiar syntax:
Cheerio implements a subset of core jQuery. Cheerio removes all the DOM inconsistencies and browser cruft from the jQuery library, revealing its truly gorgeous API.
ϟ Blazingly fast:
Cheerio works with a very simple, consistent DOM model. As a result parsing, manipulating, and rendering are incredibly efficient.
❁ Incredibly flexible:
Cheerio wraps around parse5 parser and can optionally use @FB55’s forgiving htmlparser2. Cheerio can parse nearly any HTML or XML document.
Cheerio is not a web browser
Cheerio parses markup and provides an API for traversing/manipulating the resulting data structure. It does not interpret the result as a web browser does. Specifically, it does not produce a visual rendering, apply CSS, load external resources, or execute JavaScript. This makes Cheerio much, much faster than other solutions. If your use case requires any of this functionality, you should consider projects like Puppeteer or JSDom.
API
Markup example we’ll be using:

  • Apple
  • Orange
  • Pear

This is the HTML markup we will be using in all of the API examples.
Loading
First you need to load in the HTML. This step in jQuery is implicit, since jQuery operates on the one, baked-in DOM. With Cheerio, we need to pass in the HTML document.
This is the preferred method:
// ES6 or TypeScript:
import * as cheerio from ‘cheerio’;
// In other environments:
const $ = (‘

‘);
//=>


Similar to web browser contexts, load will introduce , , and elements if they are not already present. You can set load’s third argument to false to disable this.
const $ = (‘

‘, null, false);
//=> ‘


Optionally, you can also load in the HTML by passing the string as the context:
$(‘ul’, ‘

‘);
Or as the root:
$(‘li’, ‘ul’, ‘

‘);
If you need to modify parsing options for XML input, you may pass an extra
object to ():
const $ = (‘

‘, {
xml: {
normalizeWhitespace: true, }, });
The options in the xml object are taken directly from htmlparser2, therefore any options that can be used in htmlparser2 are valid in cheerio as well. When xml is set, the default options are:
{
xmlMode: true,
decodeEntities: true, // Decode HTML entities.
withStartIndices: false, // Add a `startIndex` property to nodes.
withEndIndices: false, // Add an `endIndex` property to nodes. }
For a full list of options and their effects, see domhandler and
htmlparser2’s options.
Some users may wish to parse markup with the htmlparser2 library, and
traverse/manipulate the resulting structure with Cheerio. This may be the case
for those upgrading from pre-1. 0 releases of Cheerio (which relied on
htmlparser2), for those dealing with invalid markup (because htmlparser2 is
more forgiving), or for those operating in performance-critical situations
(because htmlparser2 may be faster in some cases). Note that “more forgiving”
means htmlparser2 has error-correcting mechanisms that aren’t always a match
for the standards observed by web browsers. This behavior may be useful when
parsing non-HTML content.
To support these cases, load also accepts a htmlparser2-compatible data
structure as its first argument. Users may install htmlparser2, use it to
parse input, and pass the result to load:
// Usage as of htmlparser2 version 6:
const htmlparser2 = require(‘htmlparser2’);
const dom = rseDocument(document, options);
const $ = (dom);
Selectors
Cheerio’s selector implementation is nearly identical to jQuery’s, so the API is very similar.
$( selector, [context], [root])
selector searches within the context scope which searches within the root scope. selector and context can be a string expression, DOM Element, array of DOM elements, or cheerio object. root is typically the HTML document string.
This selector method is the starting point for traversing and manipulating the document. Like jQuery, it’s the primary method for selecting elements in the document.
$(”, ‘#fruits’)();
//=> Apple
$(‘ul ‘)(‘class’);
//=> pear
$(‘li[class=orange]’)();
//=> Orange
XML Namespaces
You can select with XML Namespaces but due to the CSS specification, the colon (:) needs to be escaped for the selector to be valid.
Rendering
When you’re ready to render the document, you can call the html method on the “root” selection:
$()();
//=>
//
//
//

    //

  • Apple
  • //

  • Orange
  • //

  • Pear
  • //

//
//
If you want to render the outerHTML of a selection, you can use the html utility functon:
($(”));
//=>

  • Pear
  • By default, html will leave some tags open. Sometimes you may instead want to render a valid XML document. For example, you might parse the following XML snippet:
    const $ = (
    ‘);… and later want to render to XML. To do this, you can use the ‘xml’ utility function:
    //=>
    You may also render the text content of a Cheerio object using the text static method:
    const $ = (‘This is content. ‘);
    ($(‘body’));
    //=> This is content.
    Plugins
    Once you have loaded a document, you may extend the prototype or the equivalent fn property with custom plugin methods:
    const $ = (‘Hello, world! ‘);
    $. prototype. logHtml = function () {
    (());};
    $(‘body’). logHtml(); // logs “Hello, world! ” to the console
    If you’re using TypeScript, you should also add a type definition for your new method:
    declare module ‘cheerio’ {
    interface Cheerio {
    logHtml(this: Cheerio): void;}}
    The “DOM Node” object
    Cheerio collections are made up of objects that bear some resemblance to browser-based DOM nodes. You can expect them to define the following properties:
    tagName
    parentNode
    previousSibling
    nextSibling
    nodeValue
    firstChild
    childNodes
    lastChild
    Screencasts
    This video tutorial is a follow-up to Nettut’s “How to Scrape Web Pages with and jQuery”, using cheerio instead of JSDOM + jQuery. This video shows how easy it is to use cheerio and how much faster cheerio is than JSDOM + jQuery.
    Cheerio in the real world
    Are you using cheerio in production? Add it to the wiki!
    Sponsors
    Does your company use Cheerio in production? Please consider sponsoring this project! Your help will allow maintainers to dedicate more time and resources to its development and support.
    Backers
    Become a backer to show your support for Cheerio and help us maintain and improve this open source project.
    Special Thanks
    This library stands on the shoulders of some incredible developers. A special thanks to:
    • @FB55 for node-htmlparser2 & CSSSelect:
    Felix has a knack for writing speedy parsing engines. He completely re-wrote both @tautologistic’s node-htmlparser and @harry’s node-soupselect from the ground up, making both of them much faster and more flexible. Cheerio would not be possible without his foundational work
    • @jQuery team for jQuery:
    The core API is the best of its class and despite dealing with all the browser inconsistencies the code base is extremely clean and easy to follow. Much of cheerio’s implementation and documentation is from jQuery. Thanks guys.
    • @visionmedia:
    The style, the structure, the open-source”-ness” of this library comes from studying TJ’s style and using many of his libraries. This dude consistently pumps out high-quality libraries and has always been more than willing to help or answer questions. You rock TJ.
    License
    MIT
    cheerio - npm

    cheerio – npm

    Fast, flexible & lean implementation of core jQuery designed specifically for the server.
    中文文档 (Chinese Readme)
    const cheerio = require(‘cheerio’);
    const $ = (‘

    Hello world

    ‘);
    $(”)(‘Hello there! ‘);
    $(‘h2’). addClass(‘welcome’);
    $();
    //=>

    Hello there!


    Note
    We are currently working on the 1. 0. 0 release of cheerio on the main branch. The source code for the last published version, 0. 22. 0, can be found here.
    Installation
    npm install cheerio
    Features
    ❤ Familiar syntax:
    Cheerio implements a subset of core jQuery. Cheerio removes all the DOM inconsistencies and browser cruft from the jQuery library, revealing its truly gorgeous API.
    ϟ Blazingly fast:
    Cheerio works with a very simple, consistent DOM model. As a result parsing, manipulating, and rendering are incredibly efficient.
    ❁ Incredibly flexible:
    Cheerio wraps around parse5 parser and can optionally use @FB55’s forgiving htmlparser2. Cheerio can parse nearly any HTML or XML document.
    Cheerio is not a web browser
    Cheerio parses markup and provides an API for traversing/manipulating the resulting data structure. It does not interpret the result as a web browser does. Specifically, it does not produce a visual rendering, apply CSS, load external resources, or execute JavaScript. This makes Cheerio much, much faster than other solutions. If your use case requires any of this functionality, you should consider projects like Puppeteer or JSDom.
    API
    Markup example we’ll be using:

    • Apple
    • Orange
    • Pear

    This is the HTML markup we will be using in all of the API examples.
    Loading
    First you need to load in the HTML. This step in jQuery is implicit, since jQuery operates on the one, baked-in DOM. With Cheerio, we need to pass in the HTML document.
    This is the preferred method:
    // ES6 or TypeScript:
    import * as cheerio from ‘cheerio’;
    // In other environments:
    const $ = (‘

    ‘);
    //=>


    Similar to web browser contexts, load will introduce , , and elements if they are not already present. You can set load’s third argument to false to disable this.
    const $ = (‘

    ‘, null, false);
    //=> ‘


    Optionally, you can also load in the HTML by passing the string as the context:
    $(‘ul’, ‘

    ‘);
    Or as the root:
    $(‘li’, ‘ul’, ‘

    ‘);
    If you need to modify parsing options for XML input, you may pass an extra
    object to ():
    const $ = (‘

    ‘, {
    xml: {
    normalizeWhitespace: true, }, });
    The options in the xml object are taken directly from htmlparser2, therefore any options that can be used in htmlparser2 are valid in cheerio as well. When xml is set, the default options are:
    {
    xmlMode: true,
    decodeEntities: true, // Decode HTML entities.
    withStartIndices: false, // Add a `startIndex` property to nodes.
    withEndIndices: false, // Add an `endIndex` property to nodes. }
    For a full list of options and their effects, see domhandler and
    htmlparser2’s options.
    Some users may wish to parse markup with the htmlparser2 library, and
    traverse/manipulate the resulting structure with Cheerio. This may be the case
    for those upgrading from pre-1. 0 releases of Cheerio (which relied on
    htmlparser2), for those dealing with invalid markup (because htmlparser2 is
    more forgiving), or for those operating in performance-critical situations
    (because htmlparser2 may be faster in some cases). Note that “more forgiving”
    means htmlparser2 has error-correcting mechanisms that aren’t always a match
    for the standards observed by web browsers. This behavior may be useful when
    parsing non-HTML content.
    To support these cases, load also accepts a htmlparser2-compatible data
    structure as its first argument. Users may install htmlparser2, use it to
    parse input, and pass the result to load:
    // Usage as of htmlparser2 version 6:
    const htmlparser2 = require(‘htmlparser2’);
    const dom = rseDocument(document, options);
    const $ = (dom);
    Selectors
    Cheerio’s selector implementation is nearly identical to jQuery’s, so the API is very similar.
    $( selector, [context], [root])
    selector searches within the context scope which searches within the root scope. selector and context can be a string expression, DOM Element, array of DOM elements, or cheerio object. root is typically the HTML document string.
    This selector method is the starting point for traversing and manipulating the document. Like jQuery, it’s the primary method for selecting elements in the document.
    $(”, ‘#fruits’)();
    //=> Apple
    $(‘ul ‘)(‘class’);
    //=> pear
    $(‘li[class=orange]’)();
    //=> Orange
    XML Namespaces
    You can select with XML Namespaces but due to the CSS specification, the colon (:) needs to be escaped for the selector to be valid.
    Rendering
    When you’re ready to render the document, you can call the html method on the “root” selection:
    $()();
    //=>
    //
    //
    //

      //

    • Apple
    • //

    • Orange
    • //

    • Pear
    • //

    //
    //
    If you want to render the outerHTML of a selection, you can use the html utility functon:
    ($(”));
    //=>

  • Pear
  • By default, html will leave some tags open. Sometimes you may instead want to render a valid XML document. For example, you might parse the following XML snippet:
    const $ = (
    ‘);… and later want to render to XML. To do this, you can use the ‘xml’ utility function:
    //=>
    You may also render the text content of a Cheerio object using the text static method:
    const $ = (‘This is content. ‘);
    ($(‘body’));
    //=> This is content.
    Plugins
    Once you have loaded a document, you may extend the prototype or the equivalent fn property with custom plugin methods:
    const $ = (‘Hello, world! ‘);
    $. prototype. logHtml = function () {
    (());};
    $(‘body’). logHtml(); // logs “Hello, world! ” to the console
    If you’re using TypeScript, you should also add a type definition for your new method:
    declare module ‘cheerio’ {
    interface Cheerio {
    logHtml(this: Cheerio): void;}}
    The “DOM Node” object
    Cheerio collections are made up of objects that bear some resemblance to browser-based DOM nodes. You can expect them to define the following properties:
    tagName
    parentNode
    previousSibling
    nextSibling
    nodeValue
    firstChild
    childNodes
    lastChild
    Screencasts
    This video tutorial is a follow-up to Nettut’s “How to Scrape Web Pages with and jQuery”, using cheerio instead of JSDOM + jQuery. This video shows how easy it is to use cheerio and how much faster cheerio is than JSDOM + jQuery.
    Cheerio in the real world
    Are you using cheerio in production? Add it to the wiki!
    Sponsors
    Does your company use Cheerio in production? Please consider sponsoring this project! Your help will allow maintainers to dedicate more time and resources to its development and support.
    Backers
    Become a backer to show your support for Cheerio and help us maintain and improve this open source project.
    Special Thanks
    This library stands on the shoulders of some incredible developers. A special thanks to:
    • @FB55 for node-htmlparser2 & CSSSelect:
    Felix has a knack for writing speedy parsing engines. He completely re-wrote both @tautologistic’s node-htmlparser and @harry’s node-soupselect from the ground up, making both of them much faster and more flexible. Cheerio would not be possible without his foundational work
    • @jQuery team for jQuery:
    The core API is the best of its class and despite dealing with all the browser inconsistencies the code base is extremely clean and easy to follow. Much of cheerio’s implementation and documentation is from jQuery. Thanks guys.
    • @visionmedia:
    The style, the structure, the open-source”-ness” of this library comes from studying TJ’s style and using many of his libraries. This dude consistently pumps out high-quality libraries and has always been more than willing to help or answer questions. You rock TJ.
    License
    MIT
    What is cheerio js used for? - Educative.io

    What is cheerio js used for? – Educative.io

    Features of cheerio js
    Cheerio js is built over fb55’s htmlparser2, which parses HTML pages and allows the user to traverse/manipulate the resulting data structure. The syntax of cheerio js is similar to jQuery and the implementation is efficient and robust.
    Usage
    You can specify (find) elements on a web page and analyze the information depending on your use case. With this information, you can do everything you could do with objects in a programming language including counting instances of a specific object, looping through the instances to extract useful information, and more. For instance, you may want to extract all the text in the

    (or headline) tags from a web-page.
    If you’re interested in a
    Python-based​ solution for web-scraping, click here.
    Read more about cheerio in the official docs.

    Frequently Asked Questions about npm cherio

    What is NPM Cheerio?

    Cheerio js is a Javascript technology used for web-scraping in server-side implementations. Web-scraping is a scripted method of extracting data from a website that can be tailored to your use-case. NodeJS is often used as the server-side platform.

    How does Cheerio work?

    Cheerio parses markup and provides an API for traversing/manipulating the resulting data structure. It does not interpret the result as a web browser does. Specifically, it does not produce a visual rendering, apply CSS, load external resources, or execute JavaScript which is common for a SPA (single page application).

    How do you Cheerio a web scrape?

    How to Scrape a Web Page in Node Using CheerioStep 1 – Create a Working Directory. … Step 2 – Initialize the Project. … Step 3 – Install Dependencies. … Step 4 – Inspect the Web Page You Want to Scrape. … Step 5 – Write the Code to Scrape the Data.Jul 19, 2021

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