Question

我有以下代码：

print "We're going to write to a file you'll be prompted for"
targetfile = raw_input('Enter a filename: ')
targetfilefound = open('targetfile' , 'w')
print "What do we write in this file?"
targetfilefound.write("hello this is working!")
targetfilefound.close()

我创建的脚本应该能够写入用户通过raw_input定义的文件。以上可能是错误的核心，对建议持开放态度。

Answer 1

正如其他人所指出的那样，从目标文件中删除引号，因为已将其分配给变量。

但实际上，您可以使用下面给出的open，而不是编写代码

with open('somefile.txt', 'a') as the_file:
    the_file.write('hello this is working!\n')

在上述情况下，处理文件时不需要进行任何异常处理。当发生错误时，文件光标对象会自动关闭，我们不需要显式关闭它。即使它写入文件成功，它也会自动关闭文件指针引用。

Explanation of efficient use of with from Pershing Programming blog

Answer 2

根据脚本打印的内容判断，您可能希望用户输入应该打印到文件的内容，以便：

print "We're going to write to a file you'll be prompted for"
targetfile = raw_input('Enter a filename: ')
targetfilefound = open(targetfile , 'w')
print "What do we write in this file?"
targetfilefound.write(raw_input())
targetfilefound.close()

注意：如果新文件不存在，此方法将创建新文件。如果要检查文件是否存在，可以使用os模块，如下所示：

import os

print "We're going to write to a file you'll be prompted for"
targetfile = raw_input('Enter a filename: ')
if os.path.isfile(targetfile) == True:
    targetfilefound = open(targetfile , 'w')
    print "What do we write in this file?"
    targetfilefound.write(raw_input())
    targetfilefound.close()
else:
    print "File does not exist, do you want to create it? (Y/n)"
    action = raw_input('> ')
    if action == 'Y' or action == 'y':
        targetfilefound = open(targetfile , 'w')
        print "What do we write in this file?"
        targetfilefound.write(raw_input())
        targetfilefound.close()
    else:
        print "No action taken"

用于文件编写的Python raw_input

2 个答案: