201802007-二进制文件的读写方式

# wb 以二进制的方式写
f = open('hk1.log', 'wb')

f.write(bytes('中国',encoding='utf-8'))
f.close()

#rb 以二进制的方式读
f = open('hk1.log', 'rb')
a = f.read()
f.close()
print(a, type(a))
print(str(a, encoding="utf-8"))

r/w/x/a/=>字符串

rb/wb/xb/ab=>二进制

r+/w+/x+/a+/=>读写

# r+ 开始追加
f = open('hk1.log', 'r+', encoding='utf-8')
a = f.read(1)
print(a,)
print(f.tell())
a = f.read(1)
print(a,)
print(f.tell())
f.close()

# w+ 先清空,在写,后读
f = open('hk1.log', 'w+', encoding='utf-8')
f.write('你是大傻叉')
f.seek(0)
a = f.read()
f.close()
print(a)

# a+,可读,可写,内容在后面追加
f=open('hk1.log','a+',encoding='utf-8')
print(f.tell())
# f.write('sddddddd')
f.seek(0)
a=f.read()
f.close
print(a)

 

# flush 把内存内容存到硬盘里
f = open('hk1.log', 'r+', encoding='utf-8')
f.write('dfffdffd')
f.flush()
f.close()
i=input()

 

# eadline 仅读取一行数据
f = open('hk1.log', 'r+', encoding='utf-8')
a = f.readline()
f.close()
print(a)

 

# truncate 截取指定数据
f = open('hk1.log', 'r+', encoding='utf-8')
print(f.tell())
print(f.seek(6))
f.truncate()
f.close()

 

with open("hk1.log", "r)" as f
#等于f=open("hk1.log","r")

a1 = input('请输入用户名:')

a2 = input('请输入密码:')
def f1(a1, a2):
    """
    用户登陆程序
    :param a1: 用户名
    :param a2: 用户密码
    :return: 返回值

    """
    f = open('hk.log', 'r', encoding='utf-8')
    for line in f:
        line = line.strip()# 去除指定元素
        a3 = line.split('$')#在指定元素换行
        if a1 == a3[0] and a2 == a3[1]:
            return True
    return False
if f1:
    print('登陆成功')
else:
    print('登陆失败')