概要
在网络时代，图片是信息传递的重要形式之一，而Python作为一种多用途的编程语言，可以用来编写爬虫从网页上获取图片，并保存到本地。本文将介绍如何使用Python爬虫实现这一功能，并探讨一些进阶技巧。
实现
（1）请求对象定制
# 请求对象定制
def create_request(page):if 1 == page:url = 'https://sc.chinaz.com/tupian/huacaotupian.html'else:url = 'https://sc.chinaz.com/tupian/huacaotupian_' + str(page) + '.html'# 防止UA（User-Agent）检查headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko)'}request = urllib.request.Request(url=url, headers=headers)return request（2）获取网页源码
# 获取网络源码
def get_content(request):response = urllib.request.urlopen(request)content = response.read().decode('utf-8')return content
(3)解析并下载图片
# 下载
def down_load(content):tree = etree.HTML(content)name_list = tree.xpath('//div[@class="container"]//div/div/img/@alt')img_list = tree.xpath('//div[@class="container"]//div/div/img/@data-original')# for i in range(len(name_list)):# print('name', i)# for i in range(len(img_list)):# print('src', i)for i in range(len(name_list)):urllib.request.urlretrieve(url= 'https:' + img_list[i], filename='./out_Data/img/' + name_list[i] + '.png')解析网页源码这里用到了xpath，xpath是lxml下的一个包，使用时，需要导入：
from lxml import etree完整代码
完整代码如下：
import urllib.request
from lxml import etree# 分析页码之间的关系
# get请求
# https://sc.chinaz.com/tupian/huacaotupian.html 1
# https://sc.chinaz.com/tupian/huacaotupian_2.html 2
# https://sc.chinaz.com/tupian/huacaotupian_3.html 3
# https://sc.chinaz.com/tupian/huacaotupian_4.html 4# 请求对象定制
def create_request(page):if 1 == page:url = 'https://sc.chinaz.com/tupian/huacaotupian.html'else:url = 'https://sc.chinaz.com/tupian/huacaotupian_' + str(page) + '.html'# 防止UA（User-Agent）检查headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko)'}request = urllib.request.Request(url=url, headers=headers)return request# 获取网络源码
def get_content(request):response = urllib.request.urlopen(request)content = response.read().decode('utf-8')return content# 下载
def down_load(content):tree = etree.HTML(content)name_list = tree.xpath('//div[@class="container"]//div/div/img/@alt')img_list = tree.xpath('//div[@class="container"]//div/div/img/@data-original')# for i in range(len(name_list)):# print('name', i)# for i in range(len(img_list)):# print('src', i)for i in range(len(name_list)):urllib.request.urlretrieve(url= 'https:' + img_list[i], filename='./out_Data/img/' + name_list[i] + '.png')if __name__ == '__main__':start_page = int(input('请输入起始页码： '))end_page = int(input('请输入截止页码： '))for page in range(start_page, end_page + 1):print('下载至第' + page + '页')# 请求对象定制request = create_request(page)# 获取网页源码content = get_content(request)# 下载数据down_load(content)
