编写简单的爬虫程序，使用request、urlib、lxml，爬取http://www.netbian.com/页面上10幅图像，并保存到本地文件夹中

要编写一个简单的爬虫程序以爬取 http://www.netbian.com/ 页面上的10幅图像并保存到本地文件夹，我们可以按照以下步骤进行：

1. 导入所需库[^1]:

import requests
from lxml import etree
import os

2. 定义目标URL:

url = "http://www.netbian.com/"

3. 设置请求头（可能需要针对网站设置适当的User-Agent）:

headers = {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3'
}

4. 发送GET请求并获取页面内容:

try:
    response = requests.get(url, headers=headers)
    response.raise_for_status()
    print("成功获取源代码")
except requests.exceptions.RequestException as e:
    print(f"获取源代码失败: {e}")

5. 解析HTML内容找到图像元素:

tree = etree.HTML(response.text)
image_elements = tree.xpath('//img')[:10]  # 取前10个img元素

6. 保存图像到本地:

if image_elements:
    images_folder = 'images'
    if not os.path.exists(images_folder):
        os.makedirs(images_folder)

    for i, img_element in enumerate(image_elements, start=1):  # 序号从1开始
        img_url = img_element.attrib['src']
        img_name = f'image_{i}.jpg'  # 根据序号命名
        file_path = os.path.join(images_folder, img_name)

        try:
            with open(file_path, 'wb') as f:
                img_data = requests.get(img_url).content
                f.write(img_data)
                print(f"已保存图像到: {file_path}")
        except Exception as e:
            print(f"保存图像失败: {e}")
else:
    print("未找到任何图像元素")