文件读取的流程为：

打开文件-->读取数据-->关闭文件

文件打开函数为open，签名如下：

open(name, mode=None, buffering=None)

参数：

• name: 文件路径
• mode: 读取模式，常用的有 'r'-读，'w'-写，'b'-二进制，'a'-追加
• buffering: 缓存大小

有以下两种方式读取文件：

1、try...finally

try:
    f=open("/root/data.txt","r")
    print(f.read())
finally:
    if f:
        f.close()

2、with.. as

with open("/root/data.txt","r") as f:
    print(f.read())

文件可以按以下几种方式读取：

1、按字符读取

with open("data.txt","r") as f:
    print(f.read())

print("----------------")
with open("data.txt","r") as f:
    print(f.read(2))

• one
  two
  three
  four
  ----------------
  on
  

2、读取所有的行到list

print("----------------")
with open("data.txt","r") as f:
    list=f.readlines()
    print(list)

• ['one\n', 'two\n', 'three\n', 'four']

3、逐行读取

with open("data.txt","r") as f:
    line=f.readline()
    print(line)

输出：

• one
  

一个创业中的苦逼程序员