python学习第八天 文件操作 编码补充

1，文件操作。
    模特主妇护士老师.txt
    1,文件路径：d:模特主妇护士老师.txt
    2,编码方式：utf-8 gbk 。。。。
    3，操作方式：只读，只写，追加，读写，写读.....
        以什么编码方式储存的文件，就以什么编码打开进行操作。

只读：r
      rb
    f = open('模特主妇护士班主任',mode='r',encoding='utf-8')
    content = f.read()
    print(content,type(content))
    f.close()

    # f = open('模特主妇护士班主任',mode='rb',)
    # content = f.read()
    # print(content)
    # f.close()

    r+ 读写
    r+b 读写（以bytes类型）
    # f = open('log',mode='r+',encoding='utf-8')
    # print(f.read())
    # f.write('大猛，小孟')
    # f.close()

    f = open('log',mode='r+b')
    print(f.read())
    f.write('大猛，小孟'.encode('utf-8'))
    f.close()

只写：w
      wb
# 先将源文件的内容全部清除，在写。
# f = open('log',mode='w',encoding='utf-8')
# f.write('附近看到类似纠纷')
# f.close()

f = open('log',mode='wb')
f.write('附近看到类似纠纷'.encode('utf-8'))
f.close()
w+
# f = open('log',mode='w+',encoding='utf-8')
# f.write('aaa')
# f.seek(0)
# print(f.read())
# f.close()
w+b
.......


追加
    # f = open('log',mode='a',encoding='utf-8')
    # f.write('佳琪')
    # f.close()

    # f = open('log',mode='ab')
    # f.write('佳琪'.encode('utf-8'))
    # f.close()

2.文件操作程序

#绝对路径
# f = open('d:模特主妇护士班主任.txt',mode='r',encoding='UTF-8')
# content = f.read()
# print(content)
# f.close()

#bytes ---->str
# f = open('模特主妇护士班主任',mode='r',encoding='utf-8')
# content = f.read()
# f.write('fjsdlk')
# f.close()

# f = open('模特主妇护士班主任',mode='rb',)
# content = f.read()
# print(content)
# f.close()
# f = open('log',mode='r+',encoding='utf-8')
# print(f.read())
# f.close()

# f = open('log',mode='r+b')
# print(f.read())
# f.write('大猛，小孟'.encode('utf-8'))
# f.close()



#对于w:没有此文件就会创建文件
# f = open('log',mode='w',encoding='utf-8')
# f.write('骑兵步兵')
# f.close()

# 先将源文件的内容全部清除，在写。
# f = open('log',mode='w',encoding='utf-8')
# f.write('附近看到类似纠纷')
# f.close()


# f = open('log',mode='w+',encoding='utf-8')
# f.write('aaa')
# f.seek(0)
# print(f.read())
# f.close()


# f = open('log',mode='wb')
# f.write('附近看到类似纠纷'.encode('utf-8'))
# f.close()

# f = open('log',mode='a',encoding='utf-8')
# f.write('佳琪')
# f.close()
#
# f = open('log',mode='a',encoding='utf-8')
# f.write('佳琪')
# f.close()



# f = open('log',mode='a+',encoding='utf-8')
# f.write('佳琪')
# f.seek(0)
# print(f.read())
# f.close()


# f = open('log',mode='ab')
# f.write('佳琪'.encode('utf-8'))
# f.close()


#功能详解

# obj = open('log',mode='r+',encoding='utf-8')
# content = f.read(3)  # 读出来的都是字符
# f.seek(3)  # 是按照字节定光标的位置
# f.tell() 告诉你光标的位置
# print(f.tell())
# content = f.read()
# print(content)
# f.tell()
# f.readable()  # 是否刻度
# line = f.readline()  # 一行一行的读
# line = f.readlines()  # 每一行当成列表中的一个元素，添加到list中
# f.truncate(4)
# for line in f:
#     print(line)
# f.close()







# f = open('log',mode='a+',encoding='utf-8')
# f.write('佳琪')
# count = f.tell()
# f.seek(count-9)
# print(f.read(2))
# f.close()

# with open('log',mode='r+',encoding='utf-8') as f,
#         open('log',mode='w+',encoding='utf-8') as f1:

3.用文件操作完成注册、登录

username = input('请输入你要注册的用户名：')
password = input('请输入你要注册的密码：')
with open('list_of_info',mode='w',encoding='utf-8') as f:
    f.write('{}
{}'.format(username,password))
print('恭喜您，注册成功')
lis = []
i = 0
while i < 3:
    usn = input('请输入你的用户名：')
    pwd = input('请输入你的密码：')
    with open('list_of_info',mode='r+',encoding='utf-8') as f1:
        for line in f1:
            lis.append(line)
    if usn == lis[0].strip() and pwd == lis[1].strip():
        print('登录成功')
        break
    else:print('账号和密码错误')
    i+=1

4.编码补充

#str --->byte  encode 编码
# s = '二哥'
# b = s.encode('utf-8')
# print(b)
# #byte --->str decode 解码
# s1 = b.decode('utf-8')
# print(s1)


# s = 'abf'
# b = s.encode('utf-8')
# print(b)
# #byte --->str decode 解码
# s1 = b.decode('gbk')
# print(s1)