python零碎知识点笔记

1、判断对象是否可迭代的

2、返回一个随机顺序的列表

from collections import Iterable
import random
class PytestTest(object):


    # 判断一个对象是否可迭代的
    def test_iterable(self,testobj):
        res = isinstance(testobj,Iterable)
        return res


    # 返回一个随机的list
    def test_random_list(self,listobj):
        random.shuffle(listobj)
        return listobj


t = PytestTest()


res = t.test_iterable("abc")
print(res)
# True
res = t.test_random_list(["a","b","c"])
print(res)
# ['b', 'a', 'c']

 

 

3、字符串的编码encode和解码decode

from collections import Iterable
import random
import io
class PytestTest(object):


    # 判断一个对象是否可迭代的
    def test_iterable(self,testobj):
        res = isinstance(testobj,Iterable)
        return res


    # 返回一个随机的list
    def test_random_list(self,listobj):
        random.shuffle(listobj)
        return listobj

    # 对一个字符串编码操作
    def test_encode(self,data,encodetype):
        res = data.encode(encoding=encodetype)
        return res
    
    # 对一个字符串做解码操作
    def test_decode(self,data,decodetype):
        res = data.decode(encoding=decodetype)
        return res




t = PytestTest()


res = t.test_iterable("abc")
print(res)
# True
res = t.test_random_list(["a","b","c"])
print(res)
# ['b', 'a', 'c']



data = "张三"

res = t.test_encode(data=data,encodetype="utf-8")
print(res)
# b'\xe5\xbc\xa0\xe4\xb8\x89'

res = t.test_decode(data=res,decodetype="utf-8")
print(res)
# 张三

 

4、查看一个对象被引用的次数

from collections import Iterable
import random
import io
import sys
class PytestTest(object):


    # 判断一个对象是否可迭代的
    def test_iterable(self,testobj):
        res = isinstance(testobj,Iterable)
        return res


    # 返回一个随机的list
    def test_random_list(self,listobj):
        random.shuffle(listobj)
        return listobj

    # 对一个字符串编码操作
    def test_encode(self,data,encodetype):
        res = data.encode(encoding=encodetype)
        return res

    # 对一个字符串做解码操作
    def test_decode(self,data,decodetype):
        res = data.decode(encoding=decodetype)
        return res
    
    # 查看一个对象被引用的次数
    def test_refernum(self,obj):
        num = sys.getrefcount(obj)
        return num



t = PytestTest()


res = t.test_iterable("abc")
print(res)
# True
res = t.test_random_list(["a","b","c"])
print(res)
# ['b', 'a', 'c']



data = "张三"

res = t.test_encode(data=data,encodetype="utf-8")
print(res)
# b'\xe5\xbc\xa0\xe4\xb8\x89'

res = t.test_decode(data=res,decodetype="utf-8")
print(res)
# 张三

res = t.test_refernum(data)
print(res)
# 6

 

 

5、返回大写字母和小写字母的方法和计算字符串所占空间

from collections import Iterable
import random
import io
import sys
import string
class PytestTest(object):


    # 判断一个对象是否可迭代的
    def test_iterable(self,testobj):
        res = isinstance(testobj,Iterable)
        return res


    # 返回一个随机的list
    def test_random_list(self,listobj):
        random.shuffle(listobj)
        return listobj

    # 对一个字符串编码操作
    def test_encode(self,data,encodetype):
        res = data.encode(encoding=encodetype)
        return res

    # 对一个字符串做解码操作
    def test_decode(self,data,decodetype):
        res = data.decode(encoding=decodetype)
        return res

    # 查看一个对象被引用的次数
    def test_refernum(self,obj):
        num = sys.getrefcount(obj)
        return num

    
    # 返回26个大写和小写字母
    def test_letters(self):
        return string.ascii_letters
    
    # 返回26个大写字母
    def test_upperletters(self):
        return string.ascii_uppercase
    
    # 返回26个小写字母
    def test_lowerletters(self):
        return string.ascii_lowercase
    
    # 计算字符串所占的空间
    def test_space_str(self,data):
        res = sys.getsizeof(data)
        return res



t = PytestTest()


res = t.test_iterable("abc")
print(res)
# True
res = t.test_random_list(["a","b","c"])
print(res)
# ['b', 'a', 'c']



data = "张三"

res = t.test_encode(data=data,encodetype="utf-8")
print(res)
# b'\xe5\xbc\xa0\xe4\xb8\x89'

res = t.test_decode(data=res,decodetype="utf-8")
print(res)
# 张三

res = t.test_refernum(data)
print(res)
# 6

res = t.test_letters()
print(res)
# abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
res = t.test_upperletters()
print(res)
# ABCDEFGHIJKLMNOPQRSTUVWXYZ
res = t.test_lowerletters()
print(res)
# abcdefghijklmnopqrstuvwxyz

res = t.test_space_str(res)
print(res)
# 75

 

6、获取windows的ip地址和主机名

import socket
    def get_host_ip(self):
        localip = socket.gethostbyname(socket.gethostname())
        return localip
     

 

    def get_host_name(self):
        hostname = socket.gethostname()
        return hostname