Test in PowerShell code if a folder is a junction point?

Question

How can I test in PowerShell code if a folder is a junction point?

Answer 1

Take a look at this blog: https://web.archive.org/web/20190422210654/https://devblogs.microsoft.com/powershell/viewing-junctions-with-dir/

the way to do it is to copy the built in file system formatting file, modify it so that junctions are indicated, then load it with Update-FormatData:

From the Blog:

The file system formatting rules are in $pshome\FileSystem.Format.ps1xml. I copied this, then in the element [ViewDefinitions –> View –> TableControl –> TableRowEntries –> TableRowEntry –> TableColumnItems –> TableColumnItem] I changed the content of PropertyName with value of 'Mode' to the following:

 
   "$($_.Mode)$(if($_.Attributes -band [IO.FileAttributes]::ReparsePoint)
{'J'})"  

This does a bitwise AND on the DirectoryInfo object Attributes property ($_.Attributes) against the .Net System.IO.FileAttributes.ReparsePoint enum value. If the result is not zero, it displays a ‘J’ next to the other file mode attributes. Next, load the new formatting file like this:

 PS> Update-FormatData -PrependPath myFilesystem.format.ps1xml

The PrependPath parameter ensures that the new formatting file is loaded before the built-in formatting files.

Directory alink has a ‘J’ in the mode column, seems to work!

It's in the Mode column J for Junction.