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  • python io操作

    一次性读取

     1 # 读取文件
     2 
     3 # 默认打开文件的方式是只读
     4 file = None
     5 try:
     6     file = open("f:/test.sql")
     7     print(file.name)  # f:/test.sql
     8 
     9     # read是一次性读取,调用read之后会把指针移动到文件的末尾,再次调用返回空字符串
    10     content = file.read()
    11 
    12     # print("----" + file.read())
    13     print(content)
    14 except Exception as log:
    15     print("找不到文件")
    16 finally:
    17     if file:
    18         file.close()
    19 
    20 # 使用with语句,with语句会自动帮我们调用close()
    21 with open("f:/test.sql") as f:
    22     print(f.read())
    23 
    24 # 使用with 可以创建单层级文件
    25 # with open("f:/ooooooooooooooooa.sql","w") as f:
    26 #     f.write("asd")

    逐行读取

     1 # 逐行读取
     2 
     3 file = None
     4 try:
     5     file = open("f:/test.sql")
     6 
     7     line = file.readline()
     8     while line is not None and line.strip() != "":
     9         print(line)
    10         line = file.readline()
    11 
    12 except Exception as info:
    13     print("文件未找到")
    14 finally:
    15     if file is not  None:
    16         file.close()

     逐行读取并写入

     1 # 逐行读取并写入
     2 rs = None
     3 ws = None
     4 try:
     5     rs = open("f:/test.sql")
     6     ws = open("f:/test_copy.sql", "w")
     7 
     8     # 读取并写入
     9     while True:
    10         line = rs.readline()
    11 
    12         # 如果line为None或者line为空字符串
    13         if line is None or line.strip() == "": # 或者 not line
    14             break
    15         ws.write(line)
    16 
    17 
    18 except Exception as info:
    19     print(info)
    20 finally:
    21     if rs:
    22         rs.close()
    23     if ws:
    24         ws.close()

     字节流

     1 # -*- coding: utf-8 -*-
     2 # @author: Tele
     3 # @Time  : 2019/04/04 下午 12:17
     4 # 字节流读写
     5 rs = open("F:/ftp_mypc/a.flv", "rb")
     6 ws = open("f:/a_copy.flv", "wb")
     7 buffer = 1024
     8 while True:
     9     content = rs.read(buffer)
    10     if not content:
    11         break
    12     ws.write(content)
    13 
    14 if rs:
    15     rs.close()
    16 if ws:
    17     ws.close()
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  • 原文地址:https://www.cnblogs.com/tele-share/p/10533771.html
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