Question

我正在尝试将使用puppeteer的节点项目迁移到使用pyppeteer的python项目。

我在下面的javascript查询中正常工作。

const values = await page.evaluate(
        () => [...document.querySelectorAll('.table')]
            .map(element => element.getAttribute('data-options'))
    );

当我尝试在python / pyppeteer中执行相同操作时：

values = await page.evaluate('''() = > [...document.querySelectorAll('.table')]
                   .map(element= > element.getAttribute('data-options'))
    ''')

我收到此错误：

Traceback (most recent call last):
  File "/home/user/PycharmProjects/pytabledata/main.py", line 30, in <module>
    asyncio.get_event_loop().run_until_complete(main())
  File "/usr/lib/python3.6/asyncio/base_events.py", line 468, in run_until_complete
    return future.result()
  File "/home/user/PycharmProjects/pytabledata/main.py", line 23, in main
    }''')
  File "/home/user/Envs/pytabledata/lib/python3.6/site-packages/pyppeteer/page.py", line 1158, in evaluate
    return await frame.evaluate(pageFunction, *args, force_expr=force_expr)
  File "/home/user/Envs/pytabledata/lib/python3.6/site-packages/pyppeteer/frame_manager.py", line 295, in evaluate
    pageFunction, *args, force_expr=force_expr)
  File "/home/user/Envs/pytabledata/lib/python3.6/site-packages/pyppeteer/execution_context.py", line 55, in evaluate
    pageFunction, *args, force_expr=force_expr)
  File "/home/user/Envs/pytabledata/lib/python3.6/site-packages/pyppeteer/execution_context.py", line 114, in evaluateHandle
    helper.getExceptionMessage(exceptionDetails)))
pyppeteer.errors.ElementHandleError: Evaluation failed: ReferenceError: Invalid left-hand side in assignment

如何使查询在python中工作？

Answer 1

javascript代码在箭头运算符上有错别字：= >（冗余空间）。修复它们之后，代码在我的机器上运行良好：

values = await page.evaluate('''() => [...document.querySelectorAll('.table')]
                   .map(element => element.getAttribute('data-options'))
    ''')

pyppeteer和javascript查询

1 个答案: