python3之开发环境PyCharm配置

1. 安装PyCharm（安装时注意选择python），地址: https://www.jetbrains.com/pycharm/

2. 安装python 地址: https://www.python.org/

3. 打开PyCharm 菜单：File->Settings->Project:x->Project Interpreter

4.以爬虫为例，在上图搜索BeautifulSoup并安装（python3请安装BeautifulSoup4）

  实例源码如下，内容来自:https://blog.csdn.net/csdn2497242041/article/details/77170746

from urllib import request

from bs4 import BeautifulSoup  # Beautiful Soup是一个可以从HTML或XML文件中提取结构化数据的Python库



# 构造头文件，模拟浏览器访问

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

headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36'}

page = request.Request(url, headers=headers)

page_info = request.urlopen(page).read().decode('utf-8')  # 打开Url,获取HttpResponse返回对象并读取其ResposneBody



# 将获取到的内容转换成BeautifulSoup格式，并将html.parser作为解析器

soup = BeautifulSoup(page_info, 'html.parser')

# 以格式化的形式打印html

print(soup.prettify())



titles = soup.find_all('a', 'title')  # 查找所有a标签中class='title'的语句



'''

# 打印查找到的每一个a标签的string和文章链接

    for title in titles:

        print(title.string)

        print("http://www.jianshu.com" + title.get('href'))   

'''



# open()是读写文件的函数,with语句会自动close()已打开文件

with open(r"F:\Python\articles.txt","w",encoding='utf-8') as file:  # 在磁盘以只写的方式打开/创建一个名为 articles 的txt文件

    for title in titles:

        file.write(title.string + '\n')

        file.write("http://www.jianshu.com" + title.get('href') + '\n\n')