Regex for everything before last forward or backward slash

Question

I need a regex that will find everything in a string up to and including the last \\ or /.

For example, c:\\directory\\file.txt should result in c:\\directory\\

Answer 1

If you're using sed for example, you could do this to output everything before the last slash:

echo "/home/me/documents/morestuff/before_last/last" | sed s:/[^/]*$::

It will output:

/home/me/documents/morestuff/before_last

Answer 2

Try this: (Rubular)

/^(.*[\\\/])/

Explanation:

^      Start of line/string
(      Start capturing group
.*     Match any character greedily
[\\\/] Match a backslash or a forward slash
)      End the capturing group  

The matched slash will be the last one because of the greediness of the .*.

If your language supports (or requires) it, you may wish to use a different delimiter than / for the regular expression so that you don't have to escape the forward-slash.

Also, if you are parsing file paths you will probably find that your language already has a library that does this. This would be better than using a regular expression.

Answer 3

^(.*[\\\/])[^\\\/]*$