Python網絡爬蟲（1）獲取網頁

from urllib.request import urlopen
from urllib.error import HTTPError
from urllib.error import URLError
from bs4 import BeautifulSoup
def getHTML(url):
    try:
        html = urlopen(url)    
    except HTTPError as e:
        print(e)
        return None
    except URLError as e:
        print(e)
        return None
    try:
        bsObj = BeautifulSoup(html.read())
        print("Html Information Get!")
        return bsObj
    except AttributeError as e:
        print(e)
        return None

try有點像中斷 只要有錯 立馬調到except裏面

獲取一個網頁有兩種錯誤：

1，網址出錯 也就是URLError 解析出錯

2，沒有這個網址 404