Converting Get-ChildItem output to string[]

Question

I have a script that accepts a list of paths to process as an array of strings. I'm using Get-ChildItem to generate those paths. I've come across some interesting behavior in the conversion from System.IO.FileInfo objects to strings.

Example 1:

PS C:\Users\Nikhil\Documents> [string[]](Get-ChildItem .\GitHub\)
toc
toc-gh-pages
Publish gh-pages.txt

Example 2:

PS C:\Users\Nikhil\Documents> [string[]](Get-ChildItem .\GitHub\*)
C:\Users\Nikhil\Documents\GitHub\toc
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages
C:\Users\Nikhil\Documents\GitHub\Publish gh-pages.txt

Example 3: (With -Recurse, so the conversion to strings is illogical and useless)

PS C:\Users\Nikhil\Documents\GitHub> [string[]](Get-ChildItem .\toc-gh-pages -Recurse)
assets
css
lib
_layouts
_site
.gitattributes
.gitignore
index.html
_config.yml
jquery.toc.zip
docs.less
docs.min.css
google-code-prettify
jquery.toc
lang-apollo.js
...

Example 4:

PS C:\Users\Nikhil\Documents\GitHub> [string[]](Get-ChildItem .\toc-gh-pages\*.* -Recurse)
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\assets\jquery.toc.zip
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\css\docs.less
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\css\docs.min.css
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\lib\google-code-prettify\lang-apollo.js
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\lib\google-code-prettify\lang-basic.js
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\lib\google-code-prettify\lang-clj.js
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\lib\google-code-prettify\lang-css.js
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\lib\google-code-prettify\lang-dart.js
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\lib\google-code-prettify\lang-erlang.js
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\lib\google-code-prettify\lang-go.js
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\lib\google-code-prettify\lang-hs.js
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\lib\google-code-prettify\lang-lisp.js
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\lib\google-code-prettify\lang-llvm.js
C:\Users\Nikhil\Documents\GitHub\toc-gh-pages\lib\google-code-prettify\lang-lua.js
...

The addition of a wildcard to the path causes the resulting strings to be full path names, instead of just file/folder names. Why does this happen?

I understand how I can work around this behavior and get the info that I need; what I'm interested in is why this is happening, given that we're just converting System.IO.FileInfo and System.IO.DirectoryInfo objects to strings in all cases.

Solution

Logical answer:

You are casting the FileInfo objects to strings. When you do gci path, you have files and directories only from that folder. So it is ok to just convert to the name of the item.

When you are using gci path\*, it is across folders, and just converting to names is not valid, so it includes the path.

Depending on whether you want name or the full path, do this:

gci $path | select -expand Name

or

gci $path | select -expand FullName

Comments

[CB.]

Read here: stackoverflow.com/a/2744637/520612

[CB.]

possible duplicate of Mysterious different conversion to string[] of seemingly same input data

[Nikhil Dabas]

That might seem logical, but the same thing happens if I include the -Recurse switch. So the output in that case is completely useless -- just a bunch of file names with no directory names.