大家好我叫hardy
需求：爬取某个页面，并把该页面的图片下载到本地
思考：
img标签一个有多少种类型的src值？四种：1、以http开头的网络链接。2、以“//”开头网络地址。3、以“/”开头绝对路径。4、以“./”开头相对路径。当然还有其他类型，不过这个不做考虑，能力有限呀。
使用什么工具？我用requests、xpth
都有那些步骤：1、爬取网页
2、分析html并获取img中的src的值
3、获取图片
4、保存
具体实现
import requests from lxml import etree import time import os import re requests = requests.session() website_url = \'\' website_name = \'\' \'\'\' 爬取的页面 \'\'\' def html_url(url): try: head = set_headers() text = requests.get(url,headers=head) # print(text) html = etree.HTML(text.text) img = html.xpath(\'//img/@src\') # 保存图片 for src in img: src = auto_completion(src) file_path = save_image(src) if file_path == False: print(\'请求的图片路径出错，url地址为：%s\'%src) else : print(\'保存图片的地址为：%s\'%file_path) except requests.exceptions.ConnectionError as e: print(\'网络地址无法访问，请检查\') print(e) except requests.exceptions.RequestException as e: print(\'访问异常：\') print(e) \'\'\' 保存图片 \'\'\' def save_image(image_url): if not image_url: return False size = 0 number = 0 while size == 0: try: img_file = requests.get(image_url) except requests.exceptions.RequestException as e: raise e # 不是图片跳过 if check_image(img_file.headers[\'Content-Type\']): return False file_path = image_path(img_file.headers) # 保存 with open(file_path, \'wb\') as f: f.write(img_file.content) # 判断是否正确保存图片 size = os.path.getsize(file_path) if size == 0: os.remove(file_path) # 如果该图片获取超过十次则跳过 number += 1 if number >= 10: break return (file_path if (size > 0) else False) \'\'\' 自动完成url的补充 \'\'\' def auto_completion(url): global website_name,website_url #如果是http://或者https://开头直接返回 if re.match(\'|https://\',url): return url elif re.match(\'//\',url): if \'https://\' in website_name: return \'https:\'+url elif \'\' in website_name: return \'http:\' + url elif re.match(\'/\',url): return website_name+url elif re.match(\'./\',url): return website_url+url[1::] \'\'\' 图片保存的路径 \'\'\' def image_path(header): # 文件夹 file_dir = \'./save_image/\' if not os.path.exists(file_dir): os.makedirs(file_dir) # 文件名 file_name = str(time.time()) # 文件后缀 suffix = img_type(header) return file_dir + file_name + suffix \'\'\' 获取图片后缀名 \'\'\' def img_type(header): # 获取文件属性 image_attr = header[\'Content-Type\'] pattern = \'image/([a-zA-Z]+)\' suffix = re.findall(pattern,image_attr,re.IGNORECASE) if not suffix: suffix = \'png\' else : suffix = suffix[0] # 获取后缀 if re.search(\'jpeg\',suffix,re.IGNORECASE): suffix = \'jpg\' return \'.\' + suffix # 检查是否为图片类型 def check_image(content_type): if \'image\' in content_type: return False else: return True #设置头部 def set_headers(): global website_name, website_url head = { \'Host\':website_name.split(\'//\')[1], \'User-Agent\':\'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.103 Safari/537.36\', } return head if __name__ == \'__main__\': #当前的url，不包含文件名的比如index.html，用来下载当前页的页面图片(./) website_url = \'https://blog.csdn.net/kindroid/article/details\' #域名，用来下载"/"开头的图片地址 #感兴趣的朋友请帮我完善一下这个自动完成图片url的补充 website_name = \'https://blog.csdn.net\' url = \'https://blog.csdn.net/kindroid/article/details/52095833\' html_url(url)