DNS on Windows Server 2003, 3rd Edition

Enumerating Objects of a Particular Class

Now let’s enumerate all logical disks on a machine. To do so, we need to use the InstancesOf method on a WMI object pointing to the namespace of the provider that contains the class. An example should make this clear:

strComputer = "."
set objWMI = GetObject("winmgmts:\\" & strComputer & "\root\cimv2")
set objDisks = objWMI.InstancesOf("Win32_LogicalDisk")
for each objDisk in objDisks
    Wscript.Echo "DeviceID: " &  objDisk.DeviceID
    Wscript.Echo "FileSystem: " &  objDisk.FileSystem
    Wscript.Echo "FreeSpace: " & objDisk.FreeSpace
    Wscript.Echo "Name: " & objDisk.Name
    Wscript.Echo "Size: " & objDisk.Size
    WScript.Echo ""
next

Here we get a WMI object pointing to the root\CIMv2 namespace, after which we call the InstancesOf method and pass the Win32_LogicalDisk class. That method returns a collection of Win32_LogicalDisk objects, which we then iterate over with a for loop.

Since we used a for loop in the last example, we’ll show the equivalent code in Perl:

use Win32::OLE 'in';
my $strComputer = ".";
my $objWMI = Win32::OLE->GetObject("winmgmts:\\\\$strComputer\\root\\cimv2");
my $objDisks = $objWMI->InstancesOf("Win32_LogicalDisk");
for my $objDisk (in $objDisks) {
    print "DeviceID: ", $objDisk->DeviceID,"\n";
    print "FileSystem: ", $objDisk->FileSystem        ,"\n";
    print "FreeSpace: ", $objDisk->FreeSpace,"\n";
    print "Name: ", $objDisk->Name,"\n";
    print "Size: ", $objDisk->Size,"\n";
    print "\n";
}

As you can see, the Perl code is very similar to the VBScript ...