Python 读写文件

简单的实例：

写输入内容到创建的文件中：

import os
ls = os.linesep     #Win is ‘\r\n‘ and Linux is ‘\n‘
fileName = raw_input(‘Please enter your file name here:‘)

while True:
    if os.path.exists(fileName):
        print ‘The file "%s" has already existed‘ %fileName
        exit(0)
    else:
        break

print "Enter what you can type here:"

lines = list()  #Create an empty list
#lines = []
while True:
    inputLine = raw_input(‘>‘)
    if inputLine == ‘ ‘:
        break
    else:
        lines.append(inputLine)

fileHandler = open(fileName, ‘w‘)
fileHandler.writelines(‘%s%s‘ %(n, ls) for n in lines)
fileHandler.close()
print ‘Write succeed!!‘

读指定文件的内容：

 1 import os
 2 fileName = raw_input(‘Please your file name:‘)
 3 print ‘***Begin to read file.‘
 4 try:
 5     fileHandler = open(fileName, ‘r‘)
 6 except IOError, e:
 7     print "*** Open file failed:", e
 8 else:
 9     for line in fileHandler:
10         print line,                 #Notice the comma
11 finally:
12     print ‘***Begin to close file.‘
13 fileHandler.close()