简体中文（ZH-CN）English（EN）繁体中文（ZH-TW）日本語（JA）한국어（KO）Melayu（MS）Français（FR）Deutsch（DE）
Maison
Article
Questions et réponses
Cours
Sujet
Télécharger
Jeu
Dictionnaire
mises à jour récentes

Maison  >  Article  >  développement back-end  >  Comment utiliser Python pour XPath, JsonPath et bs4 ?

Comment utiliser Python pour XPath, JsonPath et bs4 ?

WBOY
WBOYavant
2023-05-09 21:04:061490parcourir

1.xpath

1.1 xpath utiliser

  • google installez le plug-in xpath à l'avance, appuyez sur ctrl + shift + x et une petite boîte noire apparaîtra

  • Install lxml library pip install lxml ‐i https://pypi.douban.com/simple# 🎜🎜#pip install lxml ‐i https://pypi.douban.com/simple

  • 导入lxml.etreefrom lxml import etree

  • etree.parse() 解析本地文件html_tree = etree.parse('XX.html')

  • etree.HTML() 服务器响应文件html_tree = etree.HTML(response.read().decode('utf‐8')

    • import lxml.etreedepuis lxml import etree

    • etree.parse( ) analyser les fichiers locaux html_tree = etree.parse('XX.html')

etree.HTML() Fichier de réponses du serveur html_tree = etree.HTML(response .read().decode('utf‐8')

  • .html_tree.xpath(chemin xpath)#🎜 🎜#

    # 🎜🎜#
    • 1.2 Syntaxe XPath de base

  • 1. Requête de chemin

Trouver tous les nœuds descendants , quelle que soit la relation hiérarchique #🎜 🎜#

Trouver un nœud enfant direct

2.

3. Requête d'attributs

//div[@id] 
//div[@id="maincontent"]

4. Requête floue

//@class

5. # 

//div[contains(@id, "he")] 
//div[starts‐with(@id, "he")]
# 🎜🎜 # 1.3 Exemple # 🎜🎜 ## 🎜🎜 ## 🎜🎜 # xpath.html # 🎜🎜 ## 🎜🎜 # 
//div/h2/text()
//div[@id="head" and @class="s_down"] 
//title | //price
# 🎜🎜 # 1.4 # 🎜🎜 # # 🎜🎜 # # Crawling la valeur de Baidu bouton de recherche
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8"/>
    <title>Title</title>
</head>
<body>
    <ul>
        <li id="l1" class="class1">北京</li>
        <li id="l2" class="class2">上海</li>
        <li id="d1">广州</li>
        <li>深圳</li>
    </ul>
</body>
</html>

1.5 Images rampantes des documents pour les webmasters
from lxml import etree

# xpath解析
# 本地文件：                                          etree.parse
# 服务器相应的数据    response.read().decode(&#39;utf-8&#39;)  etree.HTML()


tree = etree.parse(&#39;xpath.html&#39;)

# 查找url下边的li
li_list = tree.xpath(&#39;//body/ul/li&#39;)
print(len(li_list))  # 4

# 获取标签中的内容
li_list = tree.xpath(&#39;//body/ul/li/text()&#39;)
print(li_list)  # [&#39;北京&#39;, &#39;上海&#39;, &#39;广州&#39;, &#39;深圳&#39;]

# 获取带id属性的li
li_list = tree.xpath(&#39;//ul/li[@id]&#39;)
print(len(li_list))  # 3

# 获取id为l1的标签内容
li_list = tree.xpath(&#39;//ul/li[@id="l1"]/text()&#39;)
print(li_list)  # [&#39;北京&#39;]

# 获取id为l1的class属性值
c1 = tree.xpath(&#39;//ul/li[@id="l1"]/@class&#39;)
print(c1)  # [&#39;class1&#39;]

# 获取id中包含l的标签
li_list = tree.xpath(&#39;//ul/li[contains(@id, "l")]/text()&#39;)
print(li_list)  # [&#39;北京&#39;, &#39;上海&#39;]
# 获取id以d开头的标签
li_list = tree.xpath(&#39;//ul/li[starts-with(@id,"d")]/text()&#39;)
print(li_list)  # [&#39;广州&#39;]
# 获取id为l2并且class为class2的标签
li_list = tree.xpath(&#39;//ul/li[@id="l2" and @class="class2"]/text()&#39;)
print(li_list)  # [&#39;上海&#39;]
# 获取id为l2或id为d1的标签
li_list = tree.xpath(&#39;//ul/li[@id="l2"]/text() | //ul/li[@id="d1"]/text()&#39;)
print(li_list)  # [&#39;上海&#39;, &#39;广州&#39;]

2.1. pip installation#🎜🎜 #
import urllib.request
from lxml import etree
url = &#39;http://www.baidu.com&#39;
headers = {
    &#39;User-Agent&#39;: &#39;Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.0.0 Safari/537.36&#39;
}
request = urllib.request.Request(url=url, headers=headers)
response = urllib.request.urlopen(request)
content = response.read().decode(&#39;utf-8&#39;)
tree = etree.HTML(content)
value = tree.xpath(&#39;//input[@id="su"]/@value&#39;)
print(value)

2.2 Utilisation de jsonpathComment utiliser Python pour XPath, JsonPath et bs4 ?

# 需求 下载的前十页的图片
# https://sc.chinaz.com/tupian/qinglvtupian.html   1
# https://sc.chinaz.com/tupian/qinglvtupian_page.html
import urllib.request
from lxml import etree
def create_request(page):
    if (page == 1):
        url = &#39;https://sc.chinaz.com/tupian/qinglvtupian.html&#39;
    else:
        url = &#39;https://sc.chinaz.com/tupian/qinglvtupian_&#39; + str(page) + &#39;.html&#39;
    headers = {
        &#39;User-Agent&#39;: &#39;Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.159 Safari/537.36&#39;,
    }
    request = urllib.request.Request(url=url, headers=headers)
    return request
def get_content(request):
    response = urllib.request.urlopen(request)
    content = response.read().decode(&#39;utf-8&#39;)
    return content
def down_load(content):
    #     下载图片
    # urllib.request.urlretrieve(&#39;图片地址&#39;,&#39;文件的名字&#39;)
    tree = etree.HTML(content)
    name_list = tree.xpath(&#39;//div[@id="container"]//a/img/@alt&#39;)
    # 一般设计图片的网站都会进行懒加载
    src_list = tree.xpath(&#39;//div[@id="container"]//a/img/@src2&#39;)
    print(src_list)
    for i in range(len(name_list)):
        name = name_list[i]
        src = src_list[i]
        url = &#39;https:&#39; + src
        urllib.request.urlretrieve(url=url, filename=&#39;./loveImg/&#39; + name + &#39;.jpg&#39;)
if __name__ == &#39;__main__&#39;:
    start_page = int(input(&#39;请输入起始页码&#39;))
    end_page = int(input(&#39;请输入结束页码&#39;))

    for page in range(start_page, end_page + 1):
        # (1) 请求对象的定制
        request = create_request(page)
        # （2）获取网页的源码
        content = get_content(request)
        # （3）下载
        down_load(content)

Comparaison des éléments de syntaxe JSONPath et des éléments XPath correspondants :

# BeautifulSoup# 🎜 🎜#

3.1 Introduction de base

1. Installation

pip install bs4

#🎜🎜 #

2. Importer Comment utiliser Python pour XPath, JsonPath et bs4 ?

depuis bs4 import BeautifulSoup

3. 🎜#

Réponse du serveur Soupe d'objets de génération de fichiers = BeautifulSoup(response.read().decode(), 'lxml')

Soupe d'objets de génération de fichiers locaux = BeautifulSoup(open('1 .html'), 'lxml')

Remarque :

Le format d'encodage par défaut pour ouvrir les fichiers est gbk, vous devez donc le spécifier pour ouvrir Format d'encodage utf-8

3.2 Installation et création

pip install jsonpath
3.3 Positionnement du nœud#🎜🎜 #
obj = json.load(open(&#39;json文件&#39;, &#39;r&#39;, encoding=&#39;utf‐8&#39;)) 
ret = jsonpath.jsonpath(obj, &#39;jsonpath语法&#39;)

3.5 Informations sur le nœud 

{ "store": {
    "book": [
      { "category": "修真",
        "author": "六道",
        "title": "坏蛋是怎样练成的",
        "price": 8.95
      },
      { "category": "修真",
        "author": "天蚕土豆",
        "title": "斗破苍穹",
        "price": 12.99
      },
      { "category": "修真",
        "author": "唐家三少",
        "title": "斗罗大陆",
        "isbn": "0-553-21311-3",
        "price": 8.99
      },
      { "category": "修真",
        "author": "南派三叔",
        "title": "星辰变",
        "isbn": "0-395-19395-8",
        "price": 22.99
      }
    ],
    "bicycle": {
      "author": "老马",
      "color": "黑色",
      "price": 19.95
    }
  }
}
import json
import jsonpath

obj = json.load(open(&#39;jsonpath.json&#39;, &#39;r&#39;, encoding=&#39;utf-8&#39;))

# 书店所有书的作者
author_list = jsonpath.jsonpath(obj, &#39;$.store.book[*].author&#39;)
print(author_list)  # [&#39;六道&#39;, &#39;天蚕土豆&#39;, &#39;唐家三少&#39;, &#39;南派三叔&#39;]

# 所有的作者
author_list = jsonpath.jsonpath(obj, &#39;$..author&#39;)
print(author_list)  # [&#39;六道&#39;, &#39;天蚕土豆&#39;, &#39;唐家三少&#39;, &#39;南派三叔&#39;, &#39;老马&#39;]

# store下面的所有的元素
tag_list = jsonpath.jsonpath(obj, &#39;$.store.*&#39;)
print(
    tag_list)  # [[{&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;六道&#39;, &#39;title&#39;: &#39;坏蛋是怎样练成的&#39;, &#39;price&#39;: 8.95}, {&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;天蚕土豆&#39;, &#39;title&#39;: &#39;斗破苍穹&#39;, &#39;price&#39;: 12.99}, {&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;唐家三少&#39;, &#39;title&#39;: &#39;斗罗大陆&#39;, &#39;isbn&#39;: &#39;0-553-21311-3&#39;, &#39;price&#39;: 8.99}, {&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;南派三叔&#39;, &#39;title&#39;: &#39;星辰变&#39;, &#39;isbn&#39;: &#39;0-395-19395-8&#39;, &#39;price&#39;: 22.99}], {&#39;author&#39;: &#39;老马&#39;, &#39;color&#39;: &#39;黑色&#39;, &#39;price&#39;: 19.95}]

# store里面所有东西的price
price_list = jsonpath.jsonpath(obj, &#39;$.store..price&#39;)
print(price_list)  # [8.95, 12.99, 8.99, 22.99, 19.95]

# 第三个书
book = jsonpath.jsonpath(obj, &#39;$..book[2]&#39;)
print(book)  # [{&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;唐家三少&#39;, &#39;title&#39;: &#39;斗罗大陆&#39;, &#39;isbn&#39;: &#39;0-553-21311-3&#39;, &#39;price&#39;: 8.99}]

# 最后一本书
book = jsonpath.jsonpath(obj, &#39;$..book[(@.length-1)]&#39;)
print(book)  # [{&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;南派三叔&#39;, &#39;title&#39;: &#39;星辰变&#39;, &#39;isbn&#39;: &#39;0-395-19395-8&#39;, &#39;price&#39;: 22.99}]
# 	前面的两本书
book_list = jsonpath.jsonpath(obj, &#39;$..book[0,1]&#39;)
# book_list = jsonpath.jsonpath(obj,&#39;$..book[:2]&#39;)
print(
    book_list)  # [{&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;六道&#39;, &#39;title&#39;: &#39;坏蛋是怎样练成的&#39;, &#39;price&#39;: 8.95}, {&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;天蚕土豆&#39;, &#39;title&#39;: &#39;斗破苍穹&#39;, &#39;price&#39;: 12.99}]

# 条件过滤需要在（）的前面添加一个？
# 	 过滤出所有的包含isbn的书。
book_list = jsonpath.jsonpath(obj, &#39;$..book[?(@.isbn)]&#39;)
print(
    book_list)  # [{&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;唐家三少&#39;, &#39;title&#39;: &#39;斗罗大陆&#39;, &#39;isbn&#39;: &#39;0-553-21311-3&#39;, &#39;price&#39;: 8.99}, {&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;南派三叔&#39;, &#39;title&#39;: &#39;星辰变&#39;, &#39;isbn&#39;: &#39;0-395-19395-8&#39;, &#39;price&#39;: 22.99}]
# 哪本书超过了10块钱
book_list = jsonpath.jsonpath(obj, &#39;$..book[?(@.price>10)]&#39;)
print(
    book_list)  # [{&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;天蚕土豆&#39;, &#39;title&#39;: &#39;斗破苍穹&#39;, &#39;price&#39;: 12.99}, {&#39;category&#39;: &#39;修真&#39;, &#39;author&#39;: &#39;南派三叔&#39;, &#39;title&#39;: &#39;星辰变&#39;, &#39;isbn&#39;: &#39;0-395-19395-8&#39;, &#39;price&#39;: 22.99}]
3.6 Exemple d'utilisation

    bs4.html

  • 1.根据标签名查找节点 
	soup.a 【注】只能找到第一个a 
		soup.a.name 
		soup.a.attrs 
2.函数 
	(1).find(返回一个对象) 
		find(&#39;a&#39;)：只找到第一个a标签
		find(&#39;a&#39;, title=&#39;名字&#39;) 
		find(&#39;a&#39;, class_=&#39;名字&#39;) 
	(2).find_all(返回一个列表) 
		find_all(&#39;a&#39;) 查找到所有的a 
		find_all([&#39;a&#39;, &#39;span&#39;]) 返回所有的a和span 
		find_all(&#39;a&#39;, limit=2) 只找前两个a 
	(3).select(根据选择器得到节点对象)【推荐】 
		1.element 
			eg:p 
		2..class 
			eg:.firstname 
		3.#id
			eg:#firstname 
		4.属性选择器 
			[attribute] 
				eg:li = soup.select(&#39;li[class]&#39;) 
			[attribute=value] 
				eg:li = soup.select(&#39;li[class="hengheng1"]&#39;) 
		5.层级选择器 
			element element 
				div p 
			element>element 
				div>p 
			element,element 
				div,p 
					eg:soup = soup.select(&#39;a,span&#39;)
    1.根据标签名查找节点 
	soup.a 【注】只能找到第一个a 
		soup.a.name 
		soup.a.attrs 
2.函数 
	(1).find(返回一个对象) 
		find(&#39;a&#39;)：只找到第一个a标签
		find(&#39;a&#39;, title=&#39;名字&#39;) 
		find(&#39;a&#39;, class_=&#39;名字&#39;) 
	(2).find_all(返回一个列表) 
		find_all(&#39;a&#39;) 查找到所有的a 
		find_all([&#39;a&#39;, &#39;span&#39;]) 返回所有的a和span 
		find_all(&#39;a&#39;, limit=2) 只找前两个a 
	(3).select(根据选择器得到节点对象)【推荐】 
		1.element 
			eg:p 
		2..class 
			eg:.firstname 
		3.#id
			eg:#firstname 
		4.属性选择器 
			[attribute] 
				eg:li = soup.select(&#39;li[class]&#39;) 
			[attribute=value] 
				eg:li = soup.select(&#39;li[class="hengheng1"]&#39;) 
		5.层级选择器 
			element element 
				div p 
			element>element 
				div>p 
			element,element 
				div,p 
					eg:soup = soup.select(&#39;a,span&#39;)
    #🎜 🎜#3.7 Analyser le nom du produit Starbucks

    (1).获取节点内容：适用于标签中嵌套标签的结构 
	obj.string 
	obj.get_text()【推荐】 
(2).节点的属性 
	tag.name 获取标签名 
		eg:tag = find(&#39;li) 
			print(tag.name) 
	tag.attrs将属性值作为一个字典返回 
(3).获取节点属性 
	obj.attrs.get(&#39;title&#39;)【常用】 
	obj.get(&#39;title&#39;) 
	obj[&#39;title&#39;]
    • # 🎜🎜#

Ce qui précède est le contenu détaillé de. pour plus d'informations, suivez d'autres articles connexes sur le site Web de PHP en chinois!

Python html beautifulsoup pip for 对象 https
Déclaration：
Cet article est reproduit dans:. en cas de violation, veuillez contacter admin@php.cn Supprimer
Article précédent：Comment charger et traiter des fichiers Python ?Article suivant：Comment charger et traiter des fichiers Python ?

Articles Liés

Voir plus