How do I identify hashtable keys with multiple values in powershell

Question

I have a hashtable created from an array like this:

$employeesHashtable = $employees | Group-Object -Property Initials -AsHashTable

How do I find keys having multiple values?

Answer 1

The alternative to using .GetEnumerator() can be using the hash table Keys, the key collection implements ICollection and can be enumerated without issues:

$keysWithMultipleValues = $employeesHashtable.Keys.where{ $employeesHashtable[$_].Count -gt 1 }