How to refer to "\" sign in python string

Question

I have problem with refering to special symbol in string:

I have: path='C:\dir\dir1\dir2\filename.doc'

and I want filename.

When I try: filename=path[path.rfind("\"):-4]

then interpreter says it's an error line right from "\" since is treated as a comment.

Answer 1

Escape it:

filename=path[path.rfind("\\"):-4]

or better yet, use basename - part of Python's os.path library:

from os.path import basename
basename(path)

From the manual for basename:

Return the base name of pathname path. This is the second half of the pair returned by split(path). Note that the result of this function is different from the Unix basename program; where basename for '/foo/bar/' returns 'bar', the basename() function returns an empty string ('').

Answer 2

Either escape it as "\\" or use raw strings like so: r"\".

Answer 3

You can type double the \: "\".

However to split the filename out of Windows filename, use partition as os.path.split only works with /:

>>> path=r'C:\dir\dir1\dir2\filename.doc'
>>> print path.rpartition('\\')[-1]
filename.doc

Answer 4

You can use "\\", technically it would be better to use os.path.sep if you insist on using backslashes. But better yet, use / in your paths, it works fine on Windows

Python has builtin functions to manipulate paths. Note that you need to double the backslashes if you still prefer them to forwardslashes

>>> import os
>>> path='C:\\dir\\dir1\\dir2\\filename.doc'
>>> os.path.splitext(os.path.basename(path))
('filename', '.doc')

and using forwardslashes

>>> path='C:/dir/dir1/dir2/filename.doc'
>>> os.path.splitext(os.path.basename(path))
('filename', '.doc')

Answer 5

There is something about this in the FAQ: Why can’t raw strings (r-strings) end with a backslash?

If you’re trying to build Windows pathnames, note that all Windows system calls accept forward slashes too:

f = open("/mydir/file.txt")  # works fine!

If you’re trying to build a pathname for a DOS command, try e.g. one of

dir = r"\this\is\my\dos\dir" "\\"
dir = r"\this\is\my\dos\dir\ "[:-1] 
dir = "\\this\\is\\my\\dos\\dir"