Here are a few question-based titles that fit the content of your article, focusing on the key problem and solution: * **Why Does Scraping Multiple Pages with Qt\'s QWebPage Cause Crashes?** * **How

How to Avoid Crashes When Scraping Multiple Web Pages with Qt's QWebPage

Qt's QWebPage can facilitate dynamic content rendering, enabling web scraping tasks. However, attempting to load multiple pages can often result in crashes, especially if the underlying QWebPage object is not properly managed.

The Problem with Repeated Page Loading

When you repeatedly load pages using the same QWebPage instance, unexpected issues can arise due to improper object deletion. To ensure stability, it's crucial to create only one QWebPage and avoid creating multiple instances for each URL.

Solution: Creating a Reusable QWebPage

To address this, modify your code to use a single QWebPage object that can handle multiple URL loads. When each load is complete, the page will trigger an internal loop to fetch the next URL. This approach eliminates the need for multiple QApplication and QWebPage creations, which can cause crashes.

Example Code Using the Improved QWebPage

Here's an updated example that demonstrates the use of a reusable QWebPage:

<code class="python">from PyQt5.QtCore import QUrl, pyqtSignal
from PyQt5.QtWebEngineWidgets import QWebEnginePage

class WebPage(QWebEnginePage):
    htmlReady = pyqtSignal(str, str)

    def __init__(self, verbose=False):
        super().__init__()
        self._verbose = verbose
        self.loadFinished.connect(self.handleLoadFinished)

    def load_urls(self, urls):
        self._urls = iter(urls)
        self.load_next()

    def load_next(self):
        try:
            url = next(self._urls)
        except StopIteration:
            return False
        else:
            self.load(QUrl(url))
        return True

    def process_current_page(self, html):
        self.htmlReady.emit(html, self.url().toString())
        if not self.load_next():
            QApplication.instance().quit()

    def handleLoadFinished(self):
        self.toHtml(self.process_current_page)

    def javaScriptConsoleMessage(self, *args, **kwargs):
        if self._verbose:
            super().javaScriptConsoleMessage(*args, **kwargs)</code>

Usage:

<code class="python">import sys
from PyQt5.QtWidgets import QApplication

app = QApplication(sys.argv)

webpage = WebPage(verbose=False)
webpage.htmlReady.connect(my_html_processor)

urls = ['https://en.wikipedia.org/wiki/Special:Random'] * 3
webpage.load_urls(urls)

sys.exit(app.exec_())</code>

By utilizing this improved implementation, you can now scrape multiple web pages reliably without encountering crashes.

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