安装

pip install selenium webdriver-manager
# webdriver-manager auto-downloads browser drivers

基础驱动设置

from selenium import webdriver
from selenium.webdriver.chrome.service import Service
from webdriver_manager.chrome import ChromeDriverManager
driver = webdriver.Chrome(
    service=Service(ChromeDriverManager().install()))

无头模式

options = webdriver.ChromeOptions()
options.add_argument("--headless=new")
options.add_argument("--no-sandbox")
driver = webdriver.Chrome(options=options)

支持的浏览器

webdriver.Chrome()	Google Chrome / Chromium
webdriver.Firefox()	Mozilla Firefox（GeckoDriver）
webdriver.Edge()	Microsoft Edge（Chromium）
webdriver.Safari()	Apple Safari（仅 macOS）

浏览器与导航

导航

driver.get("https://example.com")
driver.back()                  # browser back
driver.forward()               # browser forward
driver.refresh()               # reload page

浏览器属性

driver.title	当前页面标题
driver.current_url	当前页面 URL
driver.page_source	完整页面 HTML 源码
driver.get_cookies()	列出所有 Cookie

窗口管理

driver.set_window_size(1920, 1080)
driver.maximize_window()
driver.minimize_window()
driver.quit()                  # close all windows, end session

查找元素

定位策略

from selenium.webdriver.common.by import By
driver.find_element(By.ID, "login-btn")
driver.find_element(By.CLASS_NAME, "nav-item")
driver.find_element(By.CSS_SELECTOR, "div.card > h2")
driver.find_element(By.XPATH, "//input[@name='q']")

By 策略

By.ID	匹配元素 id 属性
By.NAME	匹配元素 name 属性
By.CLASS_NAME	匹配 CSS class（单个类名）
By.TAG_NAME	匹配 HTML 标签名
By.CSS_SELECTOR	CSS 选择器（最灵活）
By.XPATH	XPath 表达式
By.LINK_TEXT	精确匹配链接文本
By.PARTIAL_LINK_TEXT	部分匹配链接文本

查找多个元素

items = driver.find_elements(By.CSS_SELECTOR, "li.item")
for item in items:
    print(item.text)
# Returns empty list if none found (no exception)

交互

点击与输入

elem = driver.find_element(By.ID, "search")
elem.clear()                   # clear existing text
elem.send_keys("selenium python")
elem.submit()                  # submit parent form

下拉框

from selenium.webdriver.support.ui import Select
select = Select(driver.find_element(By.ID, "country"))
select.select_by_visible_text("Canada")
select.select_by_value("ca")
select.select_by_index(2)

元素属性

.text	可见文本内容
.get_attribute('href')	HTML 属性值
.is_displayed()	元素是否可见
.is_enabled()	元素是否可交互
.is_selected()	复选框/单选框是否被选中
.tag_name	HTML 标签（如 'input'、'div'）
.value_of_css_property('color')	计算后的 CSS 属性值

等待

显式等待

from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
elem = WebDriverWait(driver, 10).until(
    EC.presence_of_element_located((By.ID, "result")))

预期条件

presence_of_element_located	元素存在于 DOM 中
visibility_of_element_located	元素在页面上可见
element_to_be_clickable	元素可见且可点击
text_to_be_present_in_element	元素包含预期文本
alert_is_present	JavaScript alert 弹出
staleness_of	元素不再在 DOM 中
title_contains	页面标题包含文本

隐式等待

driver.implicitly_wait(10)  # seconds, applies globally
# Explicit waits are preferred — more precise control

Frame 与窗口

Frame

driver.switch_to.frame("frame-name")    # by name/id
driver.switch_to.frame(0)                # by index
driver.switch_to.frame(elem)             # by element
driver.switch_to.default_content()       # back to main

窗口与标签页

original = driver.current_window_handle
driver.switch_to.new_window("tab")       # open new tab
driver.switch_to.window(original)        # switch back
driver.close()                           # close current tab

弹窗

alert = driver.switch_to.alert
print(alert.text)
alert.accept()     # click OK
alert.dismiss()    # click Cancel
alert.send_keys("input text")

截图

截取截图

driver.save_screenshot("page.png")       # full page
elem = driver.find_element(By.ID, "chart")
elem.screenshot("chart.png")             # single element

截图为 Base64

b64 = driver.get_screenshot_as_base64()
png = driver.get_screenshot_as_png()     # bytes

动作

Action 链

from selenium.webdriver.common.action_chains import ActionChains
actions = ActionChains(driver)
actions.move_to_element(menu).click().perform()

键盘动作

from selenium.webdriver.common.keys import Keys
elem.send_keys(Keys.ENTER)
elem.send_keys(Keys.CONTROL, "a")       # select all
actions.key_down(Keys.SHIFT).click(elem).perform()

鼠标动作

.click(elem)	点击元素
.double_click(elem)	双击元素
.context_click(elem)	右键点击元素
.move_to_element(elem)	悬停在元素上
.drag_and_drop(src, dst)	拖拽源元素到目标
.click_and_hold(elem)	按住鼠标按钮
.release()	释放鼠标按钮

断言

常用断言（pytest）

assert "Dashboard" in driver.title
assert driver.find_element(By.ID, "msg").text == "Done"
assert driver.current_url.endswith("/home")
assert len(driver.find_elements(By.CSS_SELECTOR, "tr")) > 0

基于等待的断言

WebDriverWait(driver, 5).until(              # appears
    EC.visibility_of_element_located((By.ID, "success")))
WebDriverWait(driver, 5).until(              # disappears
    EC.invisibility_of_element_located((By.ID, "spinner")))

JavaScript 执行

result = driver.execute_script("return document.title")
driver.execute_script(
    "arguments[0].scrollIntoView(true);", elem)

常用模式

Page Object 模式

class LoginPage:
    URL = "/login"
    user_loc = (By.ID, "username")
    def login(self, drv, user, pwd):
        drv.find_element(*self.user_loc).send_keys(user)

上下文管理器

from selenium import webdriver
with webdriver.Chrome() as driver:
    driver.get("https://example.com")
    print(driver.title)
# driver.quit() called automatically

重试与清理

try:
    driver.get("https://example.com")
    WebDriverWait(driver, 10).until(
        EC.element_to_be_clickable((By.ID, "btn")))
finally: driver.quit()

SELENIUM WEBDRIVER 快速参考