You can use the Select-Object cmdlet to create new, custom Windows PowerShell objects that contain properties selected from the objects you use to create them. Type the following command to create a new object that includes only the Name and FreeSpace properties of the Win32_LogicalDisk WMI class:
PS> Get-WmiObject -Class Win32_LogicalDisk | Select-Object -Property Name,FreeSpace Name FreeSpace ---- --------- C: 50664845312
You cannot see the type of data after issuing that command, but if you pipe the result to Get-Member after the Select-Object, you can tell that you have a new type of object, a PSCustomObject:
PS> Get-WmiObject -Class Win32_LogicalDisk | Select-Object -Property Name,FreeSpace| Get-Member TypeName: System.Management.Automation.PSCustomObject Name MemberType Definition ---- ---------- ---------- Equals Method System.Boolean Equals(Object obj) GetHashCode Method System.Int32 GetHashCode() GetType Method System.Type GetType() ToString Method System.String ToString() FreeSpace NoteProperty FreeSpace=... Name NoteProperty System.String Name=C:
Select-Object has many uses. One of them is replicating data that you can then modify. We can now handle the problem we ran across in the previous section. We can update the value of FreeSpace in our newly-created objects and the output will include the descriptive label:
Get-WmiObject -Class Win32_LogicalDisk | Select-Object -Property Name,FreeSpace | ForEach-Object -Process {$_.FreeSpace = ($_.FreeSpace)/1024.0/1024.0; $_}
Name FreeSpace
---- ---------
C: 48317.7265625