十个常见的Python脚本详细介绍及代码举例

import os

def batch_rename(directory, old_ext, new_ext):
  """批量重命名文件扩展名。

  Args:
    directory: 要处理的目录路径。
    old_ext: 要替换的旧扩展名。
    new_ext: 要替换的新扩展名。
  """

  for filename in os.listdir(directory):
    if filename.endswith(old_ext):
      base_name = os.path.splitext(filename)[0]
      new_filename = base_name + new_ext
      old_path = os.path.join(directory, filename)
      new_path = os.path.join(directory, new_filename)
      os.rename(old_path, new_path)

# 示例用法：将当前目录下所有 ".txt" 文件重命名为 ".md" 文件
batch_rename(".", ".txt", ".md")

import requests
from bs4 import BeautifulSoup
import os

def download_images(url, save_dir):
  """下载网页上的所有图片。

  Args:
    url: 要下载图片的网页地址。
    save_dir: 保存图片的目录路径。
  """

  response = requests.get(url)
  soup = BeautifulSoup(response.text, 'html.parser')

  # 创建保存目录
  if not os.path.exists(save_dir):
    os.makedirs(save_dir)

  # 找到所有图片标签
  img_tags = soup.find_all('img')

  # 下载每张图片
  for i, img_tag in enumerate(img_tags):
    img_url = img_tag.get('src')
    if img_url:
      img_data = requests.get(img_url).content
      img_name = f"image_{i+1}.jpg"
      img_path = os.path.join(save_dir, img_name)
      with open(img_path, 'wb') as f:
        f.write(img_data)
      print(f"Downloaded: {img_name}")

# 示例用法：下载百度首页的图片
download_images("https://www.baidu.com", "baidu_images")

import smtplib
from email.mime.text import MIMEText

def send_email(sender_email, sender_password, receiver_email, subject, message):
  """发送邮件通知。

  Args:
    sender_email: 发送方邮箱地址。
    sender_password: 发送方邮箱密码。
    receiver_email: 接收方邮箱地址。
    subject: 邮件主题。
    message: 邮件内容。
  """

  msg = MIMEText(message, 'plain', 'utf-8')
  msg['Subject'] = subject
  msg['From'] = sender_email
  msg['To'] = receiver_email

  try:
    with smtplib.SMTP_SSL('smtp.gmail.com', 465) as smtp:
      smtp.login(sender_email, sender_password)
      smtp.send_message(msg)
    print("邮件发送成功！")
  except Exception as e:
    print(f"邮件发送失败：{e}")

# 示例用法：发送邮件通知
send_email("your_email@gmail.com", "your_password", "receiver@example.com", "脚本执行完毕", "脚本已成功执行！")

import csv

def read_csv(file_path):
  """读取 CSV 文件。

  Args:
    file_path: CSV 文件路径。
  """

  with open(file_path, 'r', encoding='utf-8') as f:
    reader = csv.reader(f)
    # 跳过标题行
    next(reader)
    for row in reader:
      print(row)

# 示例用法：读取名为 "data.csv" 的 CSV 文件
read_csv("data.csv")

import csv

def write_csv(file_path, data):
  """将数据写入 CSV 文件。

  Args:
    file_path: CSV 文件路径。
    data: 要写入的数据，格式为列表的列表。
  """

  with open(file_path, 'w', encoding='utf-8', newline='') as f:
    writer = csv.writer(f)
    writer.writerows(data)

# 示例用法：将数据写入名为 "data.csv" 的 CSV 文件
data = [
  ["Name", "Age", "City"],
  ["Alice", 25, "New York"],
  ["Bob", 30, "London"],
]
write_csv("data.csv", data)

import requests
from bs4 import BeautifulSoup

def scrape_website(url):
  """爬取网页数据。

  Args:
    url: 要爬取数据的网页地址。
  """

  response = requests.get(url)
  soup = BeautifulSoup(response.text, 'html.parser')

  # 提取数据，例如新闻标题
  titles = [title.text.strip() for title in soup.find_all('h2', class_='news-title')]

  # 打印提取的数据
  for title in titles:
    print(title)

# 示例用法：爬取新浪新闻首页的新闻标题
scrape_website("https://news.sina.com.cn/")

from selenium import webdriver

def test_login(url, username, password):
  """测试网站登录功能。

  Args:
    url: 要测试的网站地址。
    username: 登录用户名。
    password: 登录密码。
  """

  driver = webdriver.Chrome()
  driver.get(url)

  # 找到用户名和密码输入框，并输入用户名和密码
  username_input = driver.find_element_by_id("username")
  password_input = driver.find_element_by_id("password")
  username_input.send_keys(username)
  password_input.send_keys(password)

  # 找到登录按钮，并点击
  login_button = driver.find_element_by_id("login-button")
  login_button.click()

  # 检查是否登录成功
  if driver.current_url == "https://www.example.com/dashboard":
    print("登录成功！")
  else:
    print("登录失败！")

  driver.quit()

# 示例用法：测试 example.com 网站的登录功能
test_login("https://www.example.com/login", "testuser", "testpassword")

from PIL import Image

def resize_image(image_path, width, height):
  """缩放图片大小。

  Args:
    image_path: 图片路径。
    width: 新的宽度。
    height: 新的高度。
  """

  img = Image.open(image_path)
  img = img.resize((width, height))
  img.save("resized_" + image_path)

# 示例用法：将图片 "image.jpg" 缩放为 200x200 像素
resize_image("image.jpg", 200, 200)

import matplotlib.pyplot as plt

def plot_chart(x, y):
  """绘制折线图。

  Args:
    x: x 轴数据。
    y: y 轴数据。
  """

  plt.plot(x, y)
  plt.xlabel("X 轴")
  plt.ylabel("Y 轴")
  plt.title("折线图")
  plt.show()

# 示例用法：绘制 x=[1,2,3], y=[4,5,6] 的折线图
plot_chart([1, 2, 3], [4, 5, 6])

from flask import Flask

app = Flask(__name__)

@app.route("/")
def hello():
  return "Hello, world!"

if __name__ == "__main__":
  app.run(debug=True)