python中常用的内置模块汇总

import os

# 1. 获取当前脚本绝对路径
"""
abs_path = os.path.abspath(__file__)
print(abs_path)
# 2. 获取当前文件的上级目录
base_path = os.path.dirname( os.path.dirname(路径) ）
print(base_path)
# 3. 路径拼接
p1 = os.path.join(base_path, 'xx')
print(p1)
p2 = os.path.join(base_path, 'xx', 'oo', 'a1.png')
print(p2)
# 4. 判断路径是否存在
exists = os.path.exists(p1)
print(exists)
# 5. 创建文件夹
os.makedirs(路径)
path = os.path.join(base_path, 'xx', 'oo', 'uuuu')
if not os.path.exists(path):
    os.makedirs(path)
# 6. 是否是文件夹
file_path = os.path.join(base_path, 'xx', 'oo', 'uuuu.png')
is_dir = os.path.isdir(file_path)
print(is_dir) # False
folder_path = os.path.join(base_path, 'xx', 'oo', 'uuuu')
is_dir = os.path.isdir(folder_path)
print(is_dir) # True
# 7. 删除文件或文件夹
os.remove("文件路径")
path = os.path.join(base_path, 'xx')
shutil.rmtree(path)

import os

"""
data = os.listdir("/Users/feimouren/PyCharmProjects/luffyCourse/day14/commons")
print(data)
# ['convert.py', '__init__.py', 'page.py', '__pycache__', 'utils.py', 'tencent']# 无法查看文件夹中子文件夹中的文件
要遍历一个文件夹下的所有文件，例如：遍历文件夹下的所有mp4文件  data获取到的是一个生成器，在编列生成器时，会获取到三个元素，1.文件夹路径，2.文件夹中的文件夹，3.文件  在遍历时，如果文件夹中还有文件夹，那么会继续遍历这个文件夹同样会获取三个元素。
data = os.walk("/Users/wupeiqi/Documents/视频教程/飞Python/mp4")
for path, folder_list, file_list in data:
    for file_name in file_list:
        file_abs_path = os.path.join(path, file_name)
        ext = file_abs_path.rsplit(".",1)[-1]
        if ext == "mp4":
            print(file_abs_path)

import shutil

# 1. 删除文件夹
"""
path = os.path.join(base_path, 'xx')
shutil.rmtree(path)
# 2. 拷贝文件夹
shutil.copytree("/Users/wupeiqi/Desktop/图/csdn/","/Users/wupeiqi/PycharmProjects/CodeRepository/files")
# 3.拷贝文件
shutil.copy("/Users/wupeiqi/Desktop/图/csdn/WX20201123-112406@2x.png","/Users/wupeiqi/PycharmProjects/CodeRepository/")
shutil.copy("/Users/wupeiqi/Desktop/图/csdn/WX20201123-112406@2x.png","/Users/wupeiqi/PycharmProjects/CodeRepository/x.png")
# 4.文件或文件夹重命名
shutil.move("/Users/wupeiqi/PycharmProjects/CodeRepository/x.png","/Users/wupeiqi/PycharmProjects/CodeRepository/xxxx.png")
shutil.move("/Users/wupeiqi/PycharmProjects/CodeRepository/files","/Users/wupeiqi/PycharmProjects/CodeRepository/images")
# 5. 压缩文件
# base_name，压缩后的压缩包文件
# fORMat，压缩的格式，例如："zip", "tar", "gztar", "bztar", or "xztar".
# root_dir，要压缩的文件夹路径
# shutil.make_arcHive(base_name=r'datafile',format='zip',root_dir=r'files')
# 6. 解压文件
# filename，要解压的压缩包文件
# extract_dir，解压的路径
# format，压缩文件格式
# shutil.unpack_archive(filename=r'datafile.zip', extract_dir=r'xxxxxx/xo', format='zip')

import sys

# 1. 获取解释器版本
"""
print(sys.version)
print(sys.version_info)
print(sys.version_info.major, sys.version_info.minor, sys.version_info.micro)
# 2. 导入模块路径
print(sys.path)

import random

# 1. 获取范围内的随机整数
v = random.randint(10, 20)
print(v)
# 2. 获取范围内的随机小数
v = random.uniform(1, 10)
# 3. 随机抽取一个元素
v = random.choice([11, 22, 33, 44, 55])
# 4. 随机抽取多个元素
v = random.sample([11, 22, 33, 44, 55], 3)
# 5. 打乱顺序
data = [1, 2, 3, 4, 5, 6, 7, 8, 9]
random.shuffle(data)
print(data)

import hashlib

hash_object = hashlib.md5()
hash_object.update("武沛齐".encode('utf-8'))
result = hash_object.hexdigest()
print(result)

import hashlib

hash_object = hashlib.md5("iajfsdunjaksdjfasdfasdf".encode('utf-8'))
hash_object.update("武沛齐".encode('utf-8'))
result = hash_object.hexdigest()
print(result)
"""
在加密时，为了防止密码被撞出来，通常会在第二行代码处加盐
，即添加我们自己知道的随机的字符串，这样就可以防止别人破解密码
"""

# Python中的数据类型的格式
data = [
    {"id": 1, "name": "飞某人", "age": 18},
    {"id": 2, "name": "alex", "age": 18},
    ('feimouren',123),
]

# JSON格式
value = '[{"id": 1, "name": "飞某人", "age": 18}, {"id": 2, "name": "alex", "age": 18},["feimouren",123]]'

# 实际就是将python的语法代码变成了字符串
import json

data = [
    {"id": 1, "name": "飞某人", "age": 18},
    {"id": 2, "name": "alex", "age": 18},
]
res = json.dumps(data)  # 里面的中文字符会根据unicode编码将中文转换成16进制
print(res) # [{"id": 1, "name": "\u98de\u67d0\u4eba", "age": 18}, {"id": 2, "name": "alex", "age": 18}]
res = json.dumps(data, ensure_ascii=False)     # 设置参数为False后，会保留中文
print(res) # [{"id": 1, "name": "飞某人", "age": 18}, {"id": 2, "name": "alex", "age": 18}]

""" 反序列化，将特定的字符串变成python中有语法意义的代码"""
import json

data_string = '[{"id": 1, "name": "飞某人", "age": 18}, {"id": 2, "name": "alex", "age": 18}]'
# 将字符串data_string变成了data_list列表
data_list = json.loads(data_string)
print(type(data_list), data_list)
for x in data_list:
    print(x)
"""
运行结果：
<class 'list'> [{'id': 1, 'name': '飞某人', 'age': 18}, {'id': 2, 'name': 'alex', 'age': 18}]
{'id': 1, 'name': '飞某人', 'age': 18}
{'id': 2, 'name': 'alex', 'age': 18}

+-------------------+---------------+
    | Python            | JSON          |
    +===================+===============+
    | dict              | object        |
    +-------------------+---------------+
    | list, tuple       | array         |
    +-------------------+---------------+
    | str               | string        |
    +-------------------+---------------+
    | int, float        | number        |
    +-------------------+---------------+
    | True              | true          |
    +-------------------+---------------+
    | False             | false         |
    +-------------------+---------------+
    | None              | null          |
    +-------------------+---------------+

import json
from decimal import Decimal
from datetime import datetime

data = [
    {"id": 1, "name": "武沛齐", "age": 18, 'size': Decimal("18.99"), 'ctime': datetime.now()},
    {"id": 2, "name": "alex", "age": 18, 'size': Decimal("9.99"), 'ctime': datetime.now()},
]
class MyJSONEncoder(json.JSONEncoder):
    def default(self, o):
        if type(o) == Decimal:
            return str(o)
        elif type(o) == datetime:
            return o.strftime("%Y-%M-%d")
        return super().default(o)
res = json.dumps(data, cls=MyJSONEncoder)
print(res)

"""将序列化的代码写入文件中使用dump"""
import json

data = [
    {"id": 1, "name": "飞某人", "age": 18},
    {"id": 2, "name": "alex", "age": 18},
]
file_object = open('xxx.json', mode='w', encoding='utf-8')
json.dump(data, file_object)  # 将data列表进行序列化，写入file_object.json文件中
file_object.close()

"""将文件中的特定字符串反序列化成python中的代码"""
import json
file_object = open('xxx.json', mode='r', encoding='utf-8')
data_list = json.load(file_object)
print(type(data_list),data_list)
"""
运行结果：
<class 'list'> [{'id': 1, 'name': '飞某人', 'age': 18}, {'id': 2, 'name': 'alex', 'age': 18}]
"""