string - python replace single backslash with double backslash

Question

In python, I am trying to replace a single backslash ("") with a double backslash(""). I have the following code:

directory = string.replace("C:UsersJoshDesktop20130216", "", "")

However, this gives an error message saying it doesn't like the double backslash. Can anyone help?

Answer 1

No need to use str.replace or string.replace here, just convert that string to a raw string:

>>> strs = r"C:UsersJoshDesktop20130216"
           ^
           |
       notice the 'r'

Below is the repr version of the above string, that's why you're seeing \ here. But, in fact the actual string contains just '' not \.

>>> strs
'C:\Users\Josh\Desktop\20130216'

>>> s = r"fo"
>>> s            #repr representation
'f\o'
>>> len(s)   #length is 3, as there's only one `''`
3

But when you're going to print this string you'll not get '\' in the output.

>>> print strs
C:UsersJoshDesktop20130216

If you want the string to show '\' during print then use str.replace:

>>> new_strs = strs.replace('\','\\')
>>> print new_strs
C:\Users\Josh\Desktop\20130216

repr version will now show \\:

>>> new_strs
'C:\\Users\\Josh\\Desktop\\20130216'