#PSTip Quick objects using ConvertFrom-Csv

Note: This tip requires PowerShell 2.0 or later.

PowerShell is designed to operate on objects. But, what can we do if all we have is text e.g. from a ticket body or email?

My main tool at work is PowerShell ISE and it makes converting text data into custom object relatively easy. I just put my text data in here-string in the Script Pane and let ConvertFrom-Csv do the rest. There are two possible scenarios.

In the first one I have pieces of information from the different sources and I can format it as comma-separated values and convert it easily into custom objects:

John Doe,Finance,Accountant
Marry Jonson,IT,Consultant
Andrew Smith,HR,Recruiter
'@ | ConvertFrom-Csv

In the second, and more frequent, scenario I have data that looks almost like result from Format-Table. There is no obvious delimiter: few spaces here, one space there. That forces me to clean up the data first, before I can convert it to objects:

Name        Status            IP                  
WINSRV0001  Production       
WINSRV0002  Decommissioned       
LINSRV0001  Racked         
'@ -replace ' +', ',' | ConvertFrom-Csv

The only limitation is that all properties will be strings, even if they look like numbers:

$data = @'
'@ | ConvertFrom-Csv

$data | Get-Member -MemberType Properties

	TypeName: System.Management.Automation.PSCustomObject

Name       MemberType   Definition                 
----       ----------   ----------
DiskSizeGB NoteProperty System.String DiskSizeGB=40
VM         NoteProperty System.String VM=WINVM0001 

This may result in unexpected results when sorting/ filtering:

$data | Where-Object { 
    $_.DiskSizeGB -gt 100
} | Sort-Object DiskSizeGB 

VM                                      DiskSizeGB                             
--                                      ----------
LINVM0005                               1100                                   
WINVM0003                               120                                    
LINVM0004                               15                                     
WINVM0001                               40                                     

To fix filtering we have to remember that when comparing PowerShell will always convert value on the right to the type of value on the left. For sorting we have to use a script block and convert property to a number rather than use property as a string type:

$data | Where-Object { 
    100 -lt $_.DiskSizeGB
} | Sort-Object { [int]$_.DiskSizeGB } 

VM                                      DiskSizeGB                             
--                                      ----------
WINVM0003                               120                                    
LINVM0005                               1100                                   
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