# urllib_request.py

# 導(dǎo)入urllib.request 庫(kù)
import urllib.request

# 向指定的url發(fā)送請(qǐng)求，并返回服務(wù)器響應(yīng)的類(lèi)文件對(duì)象
response = urllib.request.urlopen("http://www.baidu.com")

# 類(lèi)文件對(duì)象支持文件對(duì)象的操作方法，如read()方法讀取文件全部?jī)?nèi)容，返回字符串
html = response.read()

# 打印字符串
print (html)

# urllib_request.py

import urllib.request

# url 作為Request()方法的參數(shù)，構(gòu)造并返回一個(gè)Request對(duì)象
request = urllib.request.Request("http://www.baidu.com")

# Request對(duì)象作為urlopen()方法的參數(shù)，發(fā)送給服務(wù)器并接收響應(yīng)
response = urllib.request.urlopen(request)

html = response.read().decode()

print (html)

#urllib_request.py

import urllib.request

url = "http://www.itcast.cn"

#IE 9.0 的 User-Agent，包含在 ua_header里
ua_header = {"User-Agent" : "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0;"}

#  url 連同 headers，一起構(gòu)造Request請(qǐng)求，這個(gè)請(qǐng)求將附帶 IE9.0 瀏覽器的User-Agent
request = urllib.request.Request(url, headers = ua_header)

# 向服務(wù)器發(fā)送這個(gè)請(qǐng)求
response = urllib.request.urlopen(request)

html = response.read()
print (html)

# urllib_headers.py

import urllib.request

url = "http://www.itcast.cn"

#IE 9.0 的 User-Agent
header = {"User-Agent" : "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0;"}
request = urllib.request.Request(url, headers = header)

#也可以通過(guò)調(diào)用Request.add_header() 添加/修改一個(gè)特定的header
request.add_header("Connection", "keep-alive")

# 也可以通過(guò)調(diào)用Request.get_header()來(lái)查看header信息
# request.get_header(header_name="Connection")

response = urllib.request.urlopen(request)

print (response.code) #可以查看響應(yīng)狀態(tài)碼
html = response.read().decode()

print (html)

# urllib_add_headers.py

import urllib
import random

url = "http://www.itcast.cn"

ua_list = [
    "Mozilla/5.0 (Windows NT 6.1; ) Apple.... ",
    "Mozilla/5.0 (X11; CrOS i686 2268.111.0)... ",
    "Mozilla/5.0 (Macintosh; U; PPC Mac OS X.... ",
    "Mozilla/5.0 (Macintosh; Intel Mac OS... "
]

user_agent = random.choice(ua_list)

request = urllib.request.Request(url)

#也可以通過(guò)調(diào)用Request.add_header() 添加/修改一個(gè)特定的header
request.add_header("User-Agent", user_agent)

# get_header()的字符串參數(shù)，第一個(gè)字母大寫(xiě)，后面的全部小寫(xiě)
request.get_header("User-agent")

response = urllib.request.urlopen(requestr)

html = response.read()
print (html)