PyExecJS is a powerful Python module that bridges the gap between Python and the realm of JavaScript. This integration enables you to seamlessly execute JavaScript code withinyour Python environment, unlocking a plethora of JavaScript functionalities and libraries.

The utilization of PyExecJS proves particularly valuable in scenarios demanding the invocation of JavaScript code from Python. Such scenarios include the execution of specific JavaScript functions, the manipulation of JavaScript-generated data, and the effective interaction with JavaScript-driven web pages.

Installing PyExecJS

To harness the capabilities of PyExecJS, you can effortlessly install it via pip, the widely used Python package manager.

pip install pyexecjs

Executing JavaScript Code with PyExecJS

Engaging with PyExecJS is straightforward and intuitive. To execute a snippet of JavaScript code, you can leverage the exec() method exposed by PyExecJS.

import pyexecjs

 Create a PyExecJS context
context = pyexecjs.Context()

 Execute JavaScript code
result = context.exec("42  10")

 Access the result of the JavaScript execution
print(result)   Output: 420

Accessing JavaScript Variables and Functions

PyExecJS not only allows you to execute JavaScript code, but also provides access to JavaScript variables and functions. You can use the eval() method to retrieve the value of a JavaScript variable or call a JavaScript function.

 Access a JavaScript variable
variable_value = context.eval("Math.PI")
print(variable_value)   Output: 3.141592653589793

 Call a JavaScript function
function_result = context.call("Math.sin", 0.5)
print(function_result)   Output: 0.479425538604203

Benefits of Using PyExecJS

By incorporating PyExecJS into your Python toolkit, you can reap a multitude of benefits:

• Seamless JavaScript Integration: Effortlessly integrate JavaScript code into your Python environment, enabling you to leverage the extensive capabilities of JavaScript libraries.
• Enhanced Web Scraping: Effectively handle JavaScript-heavy web pages by executing JavaScript code to extract the desired data, unlocking a broader range of possibilities for web scraping endeavors.
• Rapid Prototyping: Accelerate your prototyping efforts by combining the simplicity of Python with the power of JavaScript, empowering you to quickly validate ideas and test concepts.
• Extensibility: Extend your Python scripts by incorporating JavaScript modules and libraries, expanding the functionality of your applications.

Conclusion

PyExecJS is an invaluable tool for harnessing the full potential of JavaScript within the Python ecosystem. Its ability to execute JavaScript code, access JavaScript variables and functions, and enable seamless web scraping opens up a world of possibilities for Python developers. Whether you seek to enhance your web scrapingcapabilities, streamline your prototyping process, or simply integrate JavaScript functionalities into your Python projects, PyExecJS empowers you to achieve your goals with efficiency and ease.

请教各位，python编写爬虫，返回http error 521怎么解决

原博主用的是PyV8执行JS代码，我换了PyExecJSimport execjsimport reimport requestsurl = HERDERS = {Host: ,User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.87 Safari/537.36,}def executejs(html):# 提取其中的JS加密函数js_string = ((r(function .*?)</script>,html))# 提取其中执行JS函数的参数js_func_arg = (rsetTimeout\(\\D+\((\d+)\)\, html)[0]js_func_name = (rfunction (\w+),js_string)[0]# 修改JS函数，使其返回Cookie内容js_string = js_(eval(qo=eval;qo(po);), return po)func = (js_string)return (js_func_name,js_func_arg)def parse_cookie(string):string = (=, )clearance = (;)[0]return {(=)[0]: (=)[1]}# 第一次访问获取动态加密的JSfirst_html = (url=url,headers=HERDERS)(utf-8)# 执行JS获取Cookiecookie_str = executejs(first_html)# 将Cookie转换为字典格式cookie = parse_cookie(cookie_str)print(cookies = ,cookie)# 带上cookies参数，再次请求response = (url=url,headers=HERDERS,cookies=cookie)print(_code)

Axure9无法调用js函数吗

可以。 与您分享如何用Python调用JS中的函数的经验技巧，具体如下：pythonPython调用JS文件中的函数方法如下：1、安装PyExecJS第三方库2、导入库：importexecjs3、调用JS。