This article mainly introduces the relevant information about Python using the Beautiful Soup module to create objects. The introduction in the article is very detailed. I believe it has certain reference value for everyone. Friends who need it can take a look below.
Installation
Install the Beautiful Soup module via pip: pip install beautifulsoup4 .
You can also use PyCharm IDE to write code. Find Project in Preferences in PyCharm, search for the Beautiful Soup module in it, and install it.
Create a BeautifulSoup object
The Beautiful Soup module is widely used to get data from web pages. We can use the Beautiful Soup module to extract any data from an HTML/XML document, for example, all links in a web page or content within tags.
To achieve this, Beautiful Soup provides different objects and methods. Any HTML/XML document can be converted into different Beautiful Soup objects. These objects have different properties and methods, and we can extract the required data from them.
Beautiful Soup has a total of three objects:
BeautifulSoup
Tag
NavigableString
Create a BeautifulSoup object
Creating a BeautifulSoup object is the starting point for any Beautiful Soup project.
BeautifulSoup can pass a string or file-like object, such as a file or web page on the machine.
Creating BeautifulSoup objects from strings
Create objects by passing a string in the constructor of BeautifulSoup.
In addition to passing file-like objects, we can also pass local file objects to the constructor of BeautifulSoup to generate objects.
with open('foo.html','r') as foo_file :
soup_foo = BeautifulSoup(foo_file)
print soup_foo
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Creating BeautifulSoup objects for XML parsing
The Beautiful Soup module can also be used to parse XML.
When creating a BeautifulSoup object, the Beautiful Soup module will select the appropriate TreeBuilder class to create the HTML/XML tree. By default, the HTML TreeBuilder object is selected, which will use the default HTML parser to produce an HTML structure tree. In the above code, the BeautifulSoup object is generated from the string by parsing it into an HTML tree structure.
If we want the Beautiful Soup module to parse the input content into XML type, then we need to accurately specify the features parameter used in the Beautiful Soup constructor. By specifying the features parameter, Beautiful Soup will select the most suitable TreeBuilder class to meet the features we want.
Understanding features parameters
Each TreeBuilder will have different features depending on the parser it uses. Therefore, the input content will have different results depending on the features parameter passed to the constructor. In the Beautiful Soup module, the parser currently used by TreeBuilder is as follows:
lxml
html5lib
html.parser
The features parameter of the BeautifulSoup constructor can accept a string list or a string value.
Currently, the features parameters and parsers supported by each TreeBuilder are as shown in the following table:
Use most text editors to open XML files; if you need a more intuitive tree display, you can use an XML editor, such as Oxygen XML Editor or XMLSpy; if you process XML data in a program, you need to use a programming language (such as Python) and XML libraries (such as xml.etree.ElementTree) to parse.
There is no simple and direct free XML to PDF tool on mobile. The required data visualization process involves complex data understanding and rendering, and most of the so-called "free" tools on the market have poor experience. It is recommended to use computer-side tools or use cloud services, or develop apps yourself to obtain more reliable conversion effects.
XML beautification is essentially improving its readability, including reasonable indentation, line breaks and tag organization. The principle is to traverse the XML tree, add indentation according to the level, and handle empty tags and tags containing text. Python's xml.etree.ElementTree library provides a convenient pretty_xml() function that can implement the above beautification process.
The speed of mobile XML to PDF depends on the following factors: the complexity of XML structure. Mobile hardware configuration conversion method (library, algorithm) code quality optimization methods (select efficient libraries, optimize algorithms, cache data, and utilize multi-threading). Overall, there is no absolute answer and it needs to be optimized according to the specific situation.
It is not easy to convert XML to PDF directly on your phone, but it can be achieved with the help of cloud services. It is recommended to use a lightweight mobile app to upload XML files and receive generated PDFs, and convert them with cloud APIs. Cloud APIs use serverless computing services, and choosing the right platform is crucial. Complexity, error handling, security, and optimization strategies need to be considered when handling XML parsing and PDF generation. The entire process requires the front-end app and the back-end API to work together, and it requires some understanding of a variety of technologies.
Modifying XML content requires programming, because it requires accurate finding of the target nodes to add, delete, modify and check. The programming language has corresponding libraries to process XML and provides APIs to perform safe, efficient and controllable operations like operating databases.
An application that converts XML directly to PDF cannot be found because they are two fundamentally different formats. XML is used to store data, while PDF is used to display documents. To complete the transformation, you can use programming languages and libraries such as Python and ReportLab to parse XML data and generate PDF documents.
It is impossible to complete XML to PDF conversion directly on your phone with a single application. It is necessary to use cloud services, which can be achieved through two steps: 1. Convert XML to PDF in the cloud, 2. Access or download the converted PDF file on the mobile phone.
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