文件的高級解决

f=open('m.txt',mode='rt',encoding='utf-8')
# res = f.read()
print(f.readable())#True
print(f.writable())#False
f.close()

f=open('b.txt',mode='wt',encoding='utf-8')
f.write("你好啊哈哈哈\n")
f.write("hello1\n")
f.write("hello2\n")
f.close()

f=open('c.txt',mode='at',encoding='utf-8')
f.write("jason:777\n")#会换行
f.write("jjj:666\n")
f.close()

# 示范1：注册功能
name = input("your name: ").strip()
# 做合法性校验：
# 1
、如果输入的用户名包含特殊字符^$&...让用户重新输入
# 2、如果输入的用户名已经存在也重新输入
pwd = input("your password: ").strip()
# 做合法性校验：
# 1	、密码长度
# 2
、如果密码包含特殊字符则重新输入
f = open('user.txt',mode='at',encoding='utf-8')
f.write('%s:%s\n' %(name,pwd))
f.close()

# 示范2：登录功能
inp_name = input("your name: ").strip()
inp_pwd = input("your pwd: ").strip()

f = open('user.txt',mode='rt',encoding='utf-8')
for line in f:
    user,pwd=line.strip('\n').split(':')#解压赋值
    if inp_name == user and inp_pwd == pwd:
        print('login successful')
        break
else:
    print('user or password error')

f.close()
# 升级需求1：同一个账号输错三次则退出
# 升级需求2：同一个账号输错三次则
，该账号则锁定10秒，即便程序被终止	，仍然计时

f=open('a.txt',mode='rt',encoding='utf-8')
f.read()
f.close()

#r
f=open('m.txt',mode='rb')
data=f.read()
print(data,type(data))#b'hello\r\n\xe4\xbd\xa0\xe5\xa5\xbd\r\n123\r\n\r\n' <class 'bytes'>
print(data.decode('utf-8'))#b模式要解码
f.close()
#w
f=open('m.txt',mode='wb')
f.write("egon".encode('utf-8'))
f.close()

src_file=input("源文件路径：").strip()
dst_file=input("目标文件路径：").strip()

with open(r'%s' %src_file,mode='rb') as src_fobj,open(r'%s' %dst_file,mode='wb') as dst_fobj:
    # data=src_fobj.read()
    for line in src_fobj:  # line=第二行内容
        dst_fobj.write(line)

with open('a.txt',mode='rt',encoding='utf-8') as f:
    line1=f.readline()
    line2=f.readline()
    line3=f.readline()
    print(line1)
    print(line2)
    print(line3)

    lines=[]
    for line in f:
        lines.append(line)

    lines=f.readlines()#for循环简写为此行
    print(lines)

with open('b.txt',mode='wt',encoding='utf-8') as f:
    lines=['111\n','222\n','333\n']
    for line in lines:
        f.write(line)
    # f.writelines(lines)#for循环简写成此行
    f.writelines("hello")

with open(r'a.txt',mode='wt',encoding='utf-8') as f:
    print(f.name) # 取的是打开文件的路径  a.txt
    print(f.closed)#False
    for i in range(100):
        f.write("%s\n" %i)
        f.flush()#实时刷新

with open('f.txt',mode='rt',encoding='utf-8') as f:
    data=f.read(6) # 6个字符
    print(data)

with open('f.txt',mode='rb') as f:
    # data=f.read(6) # 6个字节
    data=f.read(8) # 8个字节
    print(data.decode('utf-8'))

with open('f.txt',mode='rt',encoding='utf-8') as f:
    f.seek(5,0)
    print(f.tell())
    print(f.read())
    print(f.tell())
    print('='*100)
    f.seek(0,0)
    print(f.read())

with open('f.txt',mode='rb') as f:
    f.seek(3,1)
    f.seek(3,1)
    print(f.tell())
    # f.seek(2,1)
    f.seek(5,0)
    print(f.read().decode('utf-8'))

with open('f.txt',mode='rb') as f:
    f.seek(0,2)
    f.seek(-3,2)
    # print(f.tell())
    print(f.read().decode('utf-8'))

import time

for i in range(10000):
    with open('access.log',mode='at',encoding='utf-8') as f:
        t=time.strftime("%Y-%m-%d %H:%M:%S")
        content="egon给刘老师转了%s个亿" %i

        msg=f"{t} {content}\n"
        f.write(msg)
    time.sleep(3)

import time

time.strftime("%Y-%m-%d %H:%M:%S")
time.sleep(n) #n代表几秒

#读取日志程序
import time

with open('access.log', mode='rb') as f:
    f.seek(0, 2)

    while True:
        line = f.readline()
        if len(line) == 0:
            # 没有读到内容
            time.sleep(0.5)
        else:
            print(line.decode('utf-8'), end='')

with open('f.txt',mode='ab') as f:
    # f.truncate(3)
    # f.seek(-3,2)
    f.truncate()