If you've got yourself in a bit of a mess while copying files from one place to another, or if you've got a poor person's backup of stuff in another directory then you might want to compare two folders to see if they contain the same files.

The Compare-Object cmdlet lets you do this. Here is a simple example to compare the files in two directories based just on the file name.

compare-object -referenceobject (get-childitem -recurse  | where { ! $_.PSIsContainer }) -differenceobject (get-childitem 'D:\simple-backup' -recurse  | where { ! $_.PSIsContainer }) -Property Name