Python文件操作方法详解

Somehow, it seems the love I knew was always the most destructive kind
不知为何，我经历的爱情总是最具毁灭性的的那种
Yesterday when I was young
昨日当我年少轻狂

f = open("yesterday2",'r',encoding="utf-8")
#默认读取全部字符
print(f.read())
f.close()
#输出
Somehow, it seems the love I knew was always the most destructive kind
不知为何，我经历的爱情总是最具毁灭性的的那种
Yesterday when I was young
昨日当我年少轻狂
 
f = open("yesterday2",'r',encoding="utf-8")
#只读取10个字符
print(f.read(10))
f.close()
#输出
Somehow, i

f = open("yesterday2",'r',encoding="utf-8")
print(f.read(10))
#获取指针位置
print(f.tell())
f.close()
#输出
Somehow, i #读取的内容
10 #指针位置

f = open("yesterday2",'r',encoding="utf-8")
print(f.read(10))
#设置之前的指针位置
print(f.tell())
f.seek(0)
#设置之后的指针位置
print(f.tell())
f.close()
#输出
Somehow, i #读取文件的内容
10 #设置之前的指针位置
0 #设置之后的指针位置

f = open("yesterday2",'r',encoding="utf-8")
print(f.encoding)
f.close()
#输出
utf-8

f = open("yesterday2",'r',encoding="utf-8")
print(f.fileno())
f.close()
#输出
3

f = open("yesterday2",'r',encoding="utf-8")
print(f.name)
f.close()
#输出
yesterday2

f = open("yesterday2",'r',encoding="utf-8")
print(f.isatty())
f.close()
#输出
False #表示不是一个终端设备

f = open("yesterday2",'r',encoding="utf-8")
print(f.seekable())
f.close()
#输出
True

f = open("yesterday2",'r',encoding="utf-8")
print(f.readable())
f.close()
#输出
True

f = open("yesterday2",'r',encoding="utf-8")
print(f.writable())
f.close()
#输出
False #文件不可写

>>> f = open("yesterday2","w",encoding="utf-8")
#这时'hello word'在缓存中
>>> f.write("hello word")
#强刷到磁盘上
>>> f.flush()

f = open("yesterday2","r",encoding="utf-8")
f.read()
print(f.closed)
#输出
False

#没有指针
f = open("yesterday2","a",encoding="utf-8")
f.truncate(10)
f.close()
#截取结果
Somehow, i
 
#有指针
f = open("yesterday2","a",encoding="utf-8")
f.seek(5)
f.truncate(10)
f.close()
#截取结果
Somehow, i

f = open("yesterday2","w",encoding="utf-8")
f.write("Somehow, it seems the love I knew was always the most destructive kind")
f.close()

f.close()