How do I extract a file/folder_name only from a path?

问题

Unfortunately I suck at regexp. If I have a path like so:

/long/path/to/file, I just need to extact file.

If someone supplies file/ I just need file.

If someone supplies /file/, I still need just file.

I've been using stringr functions as a crutch but this seems like straight up grep territory. Help, please?

回答1:

If I understand correctly, you could use the basename function.

f <- "/long/path/to/file"
basename(f)
# [1] "file"

回答2:

What about this?

> path <- "/long/path/to/file"
> require(stringr)
> str_extract(path, "[^/]*$")
[1] "file"

来源：https://stackoverflow.com/questions/9693877/how-do-i-extract-a-file-folder-name-only-from-a-path