Python 文件操作

#!/usr/local/bin/python
#encoding:utf-8

'''
open(file,mode='r',buffering=-1,encoding=None,errors=None,newline=None,closefd=True,opener=None) -> file object
'''

#7.1.1 文件的创建
#注意win环境下路径应用/
# context = '''hello world'''
# f = open('./hello.txt','w')
# f.write(context)
# f.close()

#7.1.2 文件的读取
#1.按行读取 readline()
# readline()每次读取文件中的一行，当文件的指针移动到文件的末尾时，依然使用readline()读取文件将出现错误

# 使用readline()读取文件
# 如果把第4行改为line = f.readline(2)表示每行每次读取2个字节，直到行尾
# f= open('hello.txt','r')
# while True:
#     line = f.readline()
#     if line:
#         print (line)
#     else:
#         break
# f.close()

#2.多行读取方式readlines()
# 使用readlines()读文件
# f = open('hello.txt','r')
# lines = f.readlines()
# for line in lines:
#     print (line)
# f.close()

#3.一次性读取方式read()
# 使用read()读文件
# f = open('hello.txt','r')
# context = f.read()
# print(context)
# f.close()

# f = open('hello.txt','r')
# context = f.read(5)                 # 读取文件前5个字节的内容
# print(context)
# print(f.tell())                    # 返回文件对象当前指针位置
# context = f.read(5)                 # 继续读取5个字节内容
# print(context)
# print(f.tell())                    # 输出文件当前指针位置
# f.close()

# 7.1.3 文件的写入
# 使用writelines()写文件
# f = open('hello.txt', 'w+')
# li = ['hello world\n','hello china\n']
# f.writelines(li)
# f.close()

# 追加新的内容到文件
# f = open('hello.txt','a+')
# new_context = 'goodbye'
# f.write(new_context)
# f.close()

# 7.1.4 文件的删除
# import os
# #open('hello.txt', 'w')
# if os.path.exists('hello.txt'):
#     os.remove('hello.txt')

# 7.1.5 文件的复制
# 使用read()、write()实现复制
# 创建文件hello.txt
# src = open('hello.txt','w')
# li = ['hello world\n','hello china\n']
# src.writelines(li)
# src.close()
# # 把hello.txt复制到hello2.txt
# src = open('hello.txt','r')
# dst = open('hello2.txt','w')
# dst.write(src.read())
# src.close()
# dst.close()

# shutil模块实现文件的复制
# import shutil
# shutil.copyfile('hello.txt','hello2.txt')
# Python 2.7中shutil.copyfile()方法dst路径必须包含完整文件名
# Python 3.X中可写作shutil.copyfile('hello.txt','../')
# shutil.copyfile('hello.txt','../hello.txt')
# shutil.copyfile('hello2.txt','hello3.txt')

# 7.1.6 文件的重命名
# 修改文件名
# import os
# li = os.listdir('.')
# print (li)
# if 'hello.txt' in li:
#     os.rename('hello.txt','hi.txt')
# elif 'hi.txt' in li:
#     os.rename('hi.txt','hello.txt')

# 修改后缀名
# import os
# files = os.listdir('.')
# for filename in files:
#     pos = filename.find('.')
#     if filename[pos + 1: ]=='html':
#         newname = filename[:pos+1] + 'htm'
#         os.rename(filename,newname)

# import os
# files = os.listdir('.')
# for filename in files:
#     li = os.path.splitext(filename)
#     if li[1] == '.html':
#         newname = li[0] + '.htm'
#         os.rename(filename,newname)

# 7.1.7 文件内容的搜索和替换
# 文件的查找
# import re
#
# f1 = open('hello.txt','r')
# count = 0
# for s in f1.readlines():
#     li = re.findall('hello',s)
#     if len(li) > 0:
#         count = count + li.count('hello')
# print('查找到' + str(count) + '个hello')
# f1.close()

# 文件的替换
# f1 = open('hello.txt','r')
# f2 = open('hello2.txt','w')
# for s in f1.readlines():
#     f2.write(s.replace('hello','hi'))
# f1.close()
# f2.close()

# 7.3.1 Python的流对象
# 1. stdin

import sys

sys.stdin = open("hello.txt", "r")
for line in sys.
4000
stdin.readlines():
    print(line)

# 2. stdout

import sys

sys.stdout = open(r"./hello.txt", "a")
print("goodbye")
sys.stdout.close()

# 3. stderr

import sys, time
sys.stdeff = open("record.log", "a")
f = open(r"./hello.txt", "r")
t = time.strftime("%Y-%m-%d %X", time.localtime())
context = f.read()
if context:
    sys.stderr.write(t + " "+ context)
else:
    raise Exception, t + " 异常信息"

#7.3.2 模拟Java的输入、输出流
# 文件输入流
def FileInputStream(filename):
    try:
        f = open(filename)
        for line in f:
            for byte in line:
                yield byte
    except StopIteration, e:
        f.close()
        return
# 文件输出流
def FileOutputStream(inputStream, filename):
    try:
        f = open(filename, "w")
        while True:
            byte = inputStream.next()
            f.write(byte)
    except StopIteration, e:
        f.close()
        return
if __name__ == "__main__":
    FileOutputStream(FileInputStream("hello.txt"), "hello2.txt")
   
# 7.4 文件处理示例--文件属性浏览程序
def showFileProperties(path):
'''显示文件的属性。包括路径、大小、创建日期、最后修改时间，最后访问时间'''
    import time, os
    for root, dirs, files in os.walk(path, True):
        print("位置： " + root)
        for filename in files:
            state = os.stat(os.path.join(root, filename))
            info = "文件名： " + filename + " "
            info = info + "大小： " + ("%d" % state[-4]) + " "
            t = time.strftime("%Y-%m-%d %X", time.localtime(state[-1]))
            info = info + "创建时间： " + t + " "
            t = time.strftime("%Y-%m-%d %X", time.localtime(state[-2]))
            info = info + "最后修改时间： " + t + " "
            t = time.strftime("%Y-%m-%d %X", time.localtime(state[-3]))
            info = info + "最后访问时间： " + t + " "
            print(info)
if __name__ == "__main__":
    path = r"D:\developer\python\example\07\7.2.2"
    showFileProperties(path)