入门 - 库

安装

¥Installation

Pip

pip install --upgrade pip
pip install playwright
playwright install

Conda

conda config --add channels conda-forge
conda config --add channels microsoft
conda install playwright
playwright install

这些命令会下载 Playwright 软件包并安装 Chromium、Firefox 和 WebKit 浏览器二进制文件。要修改此行为，请参阅安装参数。

¥These commands download the Playwright package and install browser binaries for Chromium, Firefox and WebKit. To modify this behavior see installation parameters.

用法

¥Usage

安装完成后，你可以使用 Python 脚本运行 import Playwright，并启动 3 个浏览器（chromium、firefox 和 webkit）中的任意一个。

¥Once installed, you can import Playwright in a Python script, and launch any of the 3 browsers (chromium, firefox and webkit).

from playwright.sync_api import sync_playwright

with sync_playwright() as p:
    browser = p.chromium.launch()
    page = browser.new_page()
    page.goto("https://playwright.nodejs.cn")
    print(page.title())
    browser.close()

Playwright 支持两种 API 变体：同步和异步。如果你的现代项目使用 asyncio，则应该使用异步 API：

¥Playwright supports two variations of the API: synchronous and asynchronous. If your modern project uses asyncio, you should use async API:

import asyncio
from playwright.async_api import async_playwright

async def main():
    async with async_playwright() as p:
        browser = await p.chromium.launch()
        page = await browser.new_page()
        await page.goto("https://playwright.nodejs.cn")
        print(await page.title())
        await browser.close()

asyncio.run(main())

第一个脚本

¥First script

在我们的第一个脚本中，我们将导航到 https://playwright.nodejs.cn/ 并在 WebKit 中截取屏幕截图。

¥In our first script, we will navigate to https://playwright.nodejs.cn/ and take a screenshot in WebKit.

from playwright.sync_api import sync_playwright

with sync_playwright() as p:
    browser = p.webkit.launch()
    page = browser.new_page()
    page.goto("https://playwright.nodejs.cn/")
    page.screenshot(path="example.png")
    browser.close()

默认情况下，Playwright 以无头模式运行浏览器。要查看浏览器 UI，请将 headless 选项设置为 False。你还可以使用 slow_mo 来减慢执行速度。在调试工具 section 中了解更多信息。

¥By default, Playwright runs the browsers in headless mode. To see the browser UI, set headless option to False. You can also use slow_mo to slow down execution. Learn more in the debugging tools section.

firefox.launch(headless=False, slow_mo=50)

交互模式 (REPL)

¥Interactive mode (REPL)

你可以启动交互式 Python REPL：

¥You can launch the interactive python REPL:

python

然后在其中启动 Playwright 进行快速实验：

¥and then launch Playwright within it for quick experimentation:

from playwright.sync_api import sync_playwright
playwright = sync_playwright().start()
# Use playwright.chromium, playwright.firefox or playwright.webkit
# Pass headless=False to launch() to see the browser UI
browser = playwright.chromium.launch()
page = browser.new_page()
page.goto("https://playwright.nodejs.cn/")
page.screenshot(path="example.png")
browser.close()
playwright.stop()

异步 REPL，例如 asyncio REPL：

¥Async REPL such as asyncio REPL:

python -m asyncio

from playwright.async_api import async_playwright
playwright = await async_playwright().start()
browser = await playwright.chromium.launch()
page = await browser.new_page()
await page.goto("https://playwright.nodejs.cn/")
await page.screenshot(path="example.png")
await browser.close()
await playwright.stop()

Pyinstaller

你可以将 Playwright 与 Pyinstaller 结合使用来创建独立的可执行文件。

¥You can use Playwright with Pyinstaller to create standalone executables.

main.py
from playwright.sync_api import sync_playwright

with sync_playwright() as p:
    browser = p.chromium.launch()
    page = browser.new_page()
    page.goto("https://playwright.nodejs.cn/")
    page.screenshot(path="example.png")
    browser.close()

如果你希望将浏览器与可执行文件打包在一起：

¥If you want to bundle browsers with the executables:

Bash
PowerShell
Batch

PLAYWRIGHT_BROWSERS_PATH=0 playwright install chromium
pyinstaller -F main.py

$env:PLAYWRIGHT_BROWSERS_PATH="0"
playwright install chromium
pyinstaller -F main.py

set PLAYWRIGHT_BROWSERS_PATH=0
playwright install chromium
pyinstaller -F main.py

注意

将浏览器与可执行文件打包在一起将生成更大的二进制文件。建议仅打包你使用的浏览器。

¥Bundling the browsers with the executables will generate bigger binaries. It is recommended to only bundle the browsers you use.

已知问题

¥Known issues

`time.sleep()` 导致状态过时

¥time.sleep() leads to outdated state

由于 Playwright 已提供 auto-waiting，因此你很可能无需手动等待。如果你仍然依赖它，你应该使用 page.wait_for_timeout(5000) 而不是 time.sleep(5)，最好根本不要等待超时，但有时它对调试很有用。在这种情况下，请使用我们的 wait (wait_for_timeout) 方法，而不是 time 模块。这是因为我们内部依赖异步操作，而使用 time.sleep(5) 时，它们无法正确处理。

¥Most likely you don't need to wait manually, since Playwright has auto-waiting. If you still rely on it, you should use page.wait_for_timeout(5000) instead of time.sleep(5) and it is better to not wait for a timeout at all, but sometimes it is useful for debugging. In these cases, use our wait (wait_for_timeout) method instead of the time module. This is because we internally rely on asynchronous operations and when using time.sleep(5) they can't get processed correctly.

与 Windows 上的 `SelectorEventLoop` 或 `asyncio` 不兼容

¥incompatible with SelectorEventLoop of asyncio on Windows

Playwright 在子进程中运行驱动程序，因此在 Windows 上需要 ProactorEventLoop 或 asyncio，因为 SelectorEventLoop 不支持异步子进程。

¥Playwright runs the driver in a subprocess, so it requires ProactorEventLoop of asyncio on Windows because SelectorEventLoop does not supports async subprocesses.

在 Windows Python 3.7 上，Playwright 将默认事件循环设置为 ProactorEventLoop，因为它是 Python 3.8+ 上的默认设置。

¥On Windows Python 3.7, Playwright sets the default event loop to ProactorEventLoop as it is default on Python 3.8+.

线程

¥Threading

Playwright 的 API 并非线程安全的。如果你在多线程环境中使用 Playwright，则应该为每个线程创建一个 Playwright 实例。详细信息请参见线程问题。

¥Playwright's API is not thread-safe. If you are using Playwright in a multi-threaded environment, you should create a playwright instance per thread. See threading issue for more details.

安装​

Pip​

Conda​

用法​

第一个脚本​

交互模式 (REPL)​

Pyinstaller​

已知问题​

time.sleep() 导致状态过时​

与 Windows 上的 SelectorEventLoop 或 asyncio 不兼容​

线程​

安装

Pip