How can i list namespaces under the root? - powershell

Question

I want to list which things are useable under \\root\ .However i don't know how to list or see which things i can use.Because,i am beginner in the powershell.
I am coding this thing:
wmic /namespace:\root\
(But i don't know which things i can use under root.And because of this, i cannot use anything :/)
How can i list which things could be useable under root ?
If someone can help, i will be really happy :D
I tried use "/?" but it didn't help.Also i researched on google BUT again i couldn't find something useful for myself or maybe i couldn't understand their solutions.

Answer 1

There is a WMI class of __namespace you can query:
Get-WmiObject -Namespace Root -Class __Namespace | Select Name
Name
----
subscription
DEFAULT
CIMV2
msdtc
Cli
SECURITY
SecurityCenter2
RSOP
PEH
StandardCimv2
WMI
MSPS
directory
Policy
Interop
Hardware
ServiceModel
SecurityCenter
Microsoft
Appv
I would recommend reading through about WMI. It covers some of the discoverability aspects, which are important because:
In a default installation of Windows 8, there are more than 1,100 WMI classes in Root/Cimv2
Newer versions of powershell use CIM over WMI with commands like Get-CimInstance. It's not worth worrying about for now, but it's good to look into while you're learning
WMIC is a separate exe from powershell, and doesn't return powershell objects. I would avoid it unless you're stuck to command prompt

Answer 2

Cpt.Whale's answer is helpful, but is uses the deprecated WMI cmdlets (from the Get-WmiObject docs page: "Starting in PowerShell 3.0, this cmdlet has been superseded by Get-CimInstance"); similarly, wmic.exe is deprecated (see note at the top of the page). Both are deprecated in favor of the CIM cmdlets, so the standard advice applies:
The CIM cmdlets (e.g., Get-CimInstance) superseded the WMI cmdlets (e.g., Get-WmiObject) in PowerShell v3 (released in September 2012). Therefore, the WMI cmdlets should be avoided, not least because PowerShell (Core) v7+, where all future effort will go, doesn't even have them anymore. Note that WMI still underlies the CIM cmdlets, however.
For more information, including the differences between these two sets of cmdlets, see this answer.
Thus, here are solutions based on the CIM cmdlets:
To get all namespaces nested inside another namespace, such as root:
Get-CimInstance -Class __Namespace -Namespace root | ForEach-Object Name
To get all classes inside a given namespace, such as root, by name:
Get-CimClass -Namespace root | ForEach-Object CimClassName
Note:
Append | Sort-Object to the commands above to get alphabetically sorted output.
The default namespace (also for the WMI cmdlets) is root/cimv2, which applies if you omit a -Namespace argument.