关于Python的：PyQt4到PyQt5 – ＆gt; 不推荐使用mainFrame（），需要修复以加载网页

PyQt4 to PyQt5 -> mainFrame() deprecated, need fix to load web pages

我正在做Sentdex的Pyqt4 YouTube教程。我试着跟着去，但是用Pyqt5代替。这是一个简单的网页抓取应用程序。我跟随Sentdex的教程来到这里：

enter image description here

现在我尝试用pyqt5编写相同的应用程序，这就是我所拥有的：

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import os
import sys
from PyQt5.QtWidgets import QApplication
from PyQt5.QtCore import QUrl, QEventLoop
from PyQt5.QtWebEngineWidgets import QWebEnginePage
from bs4 import BeautifulSoup
import requests

class Client(QWebEnginePage):
def __init__(self, url):
self.app = QApplication(sys.argv)
QWebEnginePage.__init__(self)
self.loadFinished.connect(self._loadFinished)
self.load(QUrl(url))
self.app.exec_()

def _loadFinished(self):
self.app.quit()

url = 'https://pythonprogramming.net/parsememcparseface/'
client_response = Client(url)

#I think the issue is here at LINE 26
source = client_response.mainFrame().toHtml()

soup = BeautifulSoup(source,"html.parser")
js_test = soup.find('p', class_='jstest')
print(js_test.text)

当我运行此程序时，我收到消息：

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source = client_response.mainFrame().toHtml()
AttributeError: 'Client' object has no attribute 'mainFrame'

我试过几种不同的解决方案，但都没用。任何帮助都将不胜感激。

编辑

第15行的logging qurl(url)返回该值：

PyQt5.QtCore.QUrl('https://pythonprogramming.net/parsememcparseface/')

当我尝试在26号线使用source = client_response.load(QUrl(url))时，我得到的信息是：

File"test3.py", line 28, in
soup = BeautifulSoup(source,"html.parser")
File"/Users/MYNAME/.venv/qtproject/lib/python3.6/site-packages/bs4/__init__.py", line 192, in __init__
elif len(markup) <= 256 and ( TypeError: object of type 'NoneType' has no len()

当我尝试source = client_response.url()时，我得到：

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soup = BeautifulSoup(source,"html.parser")
File"/Users/MYNAME/.venv/qtproject/lib/python3.6/site-packages/bs4/__init__.py", line 192, in __init__
elif len(markup) <= 256 and (
TypeError: object of type 'QUrl' has no len()

相关讨论

必须在类的定义中调用QWebEnginePage::toHtml()。QWebEnginePage::toHtml()接受一个指针函数或lambda作为参数，而这个指针函数又必须接受一个"str"类型的参数(这是包含页面HTML的参数)。下面是示例代码。

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import bs4 as bs
import sys
import urllib.request
from PyQt5.QtWebEngineWidgets import QWebEnginePage
from PyQt5.QtWidgets import QApplication
from PyQt5.QtCore import QUrl

class Page(QWebEnginePage):
def __init__(self, url):
self.app = QApplication(sys.argv)
QWebEnginePage.__init__(self)
self.html = ''
self.loadFinished.connect(self._on_load_finished)
self.load(QUrl(url))
self.app.exec_()

def _on_load_finished(self):
self.html = self.toHtml(self.Callable)
print('Load finished')

def Callable(self, html_str):
self.html = html_str
self.app.quit()

def main():
page = Page('https://pythonprogramming.net/parsememcparseface/')
soup = bs.BeautifulSoup(page.html, 'html.parser')
js_test = soup.find('p', class_='jstest')
print js_test.text

if __name__ == '__main__': main()