Start with two sentences of BB
Do you need to manually save the images one by one?
Life is short, I use Python
Here are two meme-filled URLs:
Dou Tu La
Doutu.com
Crawling emoticons, take out the key codes used and briefly talk about them.
After all, I’m not very familiar with Python, so I’ll just record what I use.
General idea:
- Send a get request through
requests.get() - Get the
crawledweb page data, and then find the emoticons in it Savethe emoticon package to a local folder
Knowledge points:
1.requests library
requests.get()
Send get request
Installation
pip install requests
Introduction
import requests
requests get request with request parameters
url = 'http://www.bbsnet.com/biaoqingbao' res = requests.get(url)
Modify encoding:
response.content.deocde(“utf-8”)
js
Copy code
html = res.content.decode(('utf-8'))
2.Usage of etree class in lxml module
Installation
pip install lxml
Introduction
from lxml import etree
Use etree.HTML() to convert html string into element object
tree = etree.HTML(html)
xpath method of element object
The Element object has an xpath method that returns a list of results and can accept bytes type data and str type data.
The full name of xpath: XML Path Language is a small query language
Is a language for finding information in XML documents
Advantages of XPath:
Information can be found in XML
Supports HTML search
Navigable via elements and attributes
According to the crawled web page data, the analysis shows that the emoticon picture is in the list with the id of post_container, and the location of the emoticon can be accurately found through xpath.
li_list = tree.xpath('//ul[@id="post_container"]/li')
3.Python “{}.format()” output formatting method
Starting with Python 2.6, a new function str.format() has been added to format strings, which enhances the string formatting function.
Example:
"{0} {1}".format("hello", "world") # Set the specified location
You can also set parameters:
print("Website name: {name}, address {url}".format(name="bilibili", url="https://www.bilibili.com/"))
4.with open() as f: usage
The open() function in Python is used to open a file and create a file object. Only related methods can call it for reading and writing.
with keyword
The file stream can be closed after the statement ends. Without the with keyword, the file will be closed by python garbage collection. Don’t use with, remember f.close()
Common usage:
with open(r'filename.txt') as f:
for l in f:
l = json.loads(l) #File reading operation
with open('Hello.txt', 'w') as f:
f.write('hello world') #File writing operation
Identifier
with open('Hello.txt', 'w') as f: # is the identifier
The meaning of common identifiers
r: Open the file in read-only mode. rb: Open a file in binary format for reading only. r + : Open a file for reading and writing. The file pointer will be placed at the beginning of the file. rb +: Open a file in binary format for reading and writing. w: Open a file for writing only. If the file already exists, it is overwritten. If the file does not exist, create a new file. wb: Open a file in binary format for writing only. If the file already exists, it is overwritten. If the file does not exist, create a new file. w + : Open a file for reading and writing. If the file already exists, it is overwritten. If the file does not exist, create a new file. wb +: Open a file in binary format for reading and writing. If the file already exists, it is overwritten. If the file does not exist, create a new file. a: Open a file for appending. If the file already exists, the file pointer will be placed at the end of the file. In other words, new content will be written after existing content. If the file does not exist, create a new file for writing. ab: Open a file in binary format for appending. If the file already exists, the file pointer will be placed at the end of the file. In other words, new content will be written after existing content. If the file does not exist, create a new file for writing. a + : Open a file for reading and writing. If the file already exists, the file pointer will be placed at the end of the file. The file will be opened in append mode. If the file does not exist, a new file is created for reading and writing. ab +: Open a file in binary format for appending. If the file already exists, the file pointer will be placed at the end of the file. If the file does not exist, a new file is created for reading and writing.
Method attributes of f:
file.read([size]) #Return file data as a string. The optional parameter size controls the number of bytes read. file.readlines([size]) #Return a list of line contents in the file, the size parameter is optional file.write(str) #Write string to file file.writelines(strings) #Write string sequence to file file.close() #Close the file file.closed #Indicates that the file has been closed, otherwise it is False file.mode #AccessThe access mode used when opening a file file.encoding #The encoding used by the file file.name #file name file.newlines #None when no line delimiter is read, a string when there is only one line delimiter, and a string containing all currently encountered lines when the file has multiple types of line terminators. end list file.softspace #0 means adding a space character after outputting a data, 1 means not adding it. This attribute is generally not used by programmers and is used internally by the program.
Results
Run the Python file, and as you wish, the emoticon package will run into my folder.
Tips
In addition to this, you can also install extensions on your Chrome browser.
Plug-in: ImageAssistant batch image download.
Downloading through plug-ins is much faster than Python crawling emoticons.
Life is short, I use ImageAssistant
Don’t waste your precious time learning Python
Manual dog head.
Final words
If the above is useful to you, you might as well like, collect and follow it, thank you
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