Powershell. count the number of duplicate entries in a file

Question

I have a text file with a list of IP addresses, and i need to count the number of times the same IP appears in the file.

I've found lots of ways of removing duplicate entries, and how to count the number of lines, but nothing on how to counting duplicate entries.

I haven't got much of a script yet, not anything worth posting, but if someone can point me in the right direction, that will be a start.

Answer 1

If $file contains

10.1.1.2  
10.1.1.2  
10.1.1.2  
10.1.1.10  
10.1.1.10  
10.1.1.20

then

Get-Content $file | Group-Object -noelement

Count Name                     
----- ----                     
3     10.1.1.2                 
2     10.1.1.10                
1     10.1.1.20