Running PowerShell Commands
The command Get-Verb is an example of a cmdlet (pronounced "command-let"). Cmdlets are structured verb-noun, where the noun is singular.
Below we will get a list of approved verbs in PowerShell, then format the results to fill the screen from left to right:
PS C:\> Get-Verb | Format-Wide -AutoSize Add Clear Close Copy Enter Exit Find Format Get Hide Join Lock Move New Open Optimize Pop Push Redo Remove Rename Reset Resize Search Select Set Show Skip Split Step Switch Undo Unlock Watch Backup Checkpoint Compare Compress Convert ConvertFrom ConvertTo Dismount Edit Expand Export Group Import Initialize Limit Merge Mount Out Publish Restore Save Sync Unpublish Update Approve Assert Complete Confirm Deny Disable Enable Install Invoke Register Request Restart Resume Start Stop Submit Suspend Uninstall Unregister Wait Debug Measure Ping Repair Resolve Test Trace Connect Disconnect Read Receive Send Write Block Grant Protect Revoke Unblock Unprotect Use
Microsoft has provided a nice page on the verb naming rules which can be found here.
The commands you use in cmd.exe can also be used within PowerShell since they are either aliased, new functions, or the external executable is called.
- dir is an alias for Get-ChildItem
- md is an alias for mkdir which is a function for New-Item
- rmdir is an alias for Remove-Item
- Get-Process
- Get-Service
- Get-Date
- Get-HotFix
- Get-History
- Start-Transcript, Stop-Transcript
- Get-ChildItem
PS C:\> Get-PSDrive Name Used (GB) Free (GB) Provider Root CurrentLocation ---- --------- --------- -------- ---- --------------- Alias Alias C 81.37 151.42 FileSystem C:\ Cert Certificate \ E FileSystem E:\ Env Environment Function Function HKCU Registry HKEY_CURRENT_USER HKLM Registry HKEY_LOCAL_MACHINE I 1112.16 305.87 FileSystem \\chs-fs01_users\Users\Michael.West Variable Variable WSMan WSMan Y 8.88 3.12 FileSystem \\chs\data
PowerShell uses a variety of providers such as those for connecting to the file system and the registry. This design allows one to use for example, the Remove-Item command to delete a file or delete a registry key. Sweet!
PS C:\> $item = New-Object -TypeName PSObject -Property @{Name="Michael";Height=73;}
PS C:\> $item | Format-List
Height : 73
Name : Michael
Here I created a new PSObject to contains some details about my name and height. Let's see the member information.
PS C:\> $item | Get-Member TypeName: System.Management.Automation.PSCustomObject Name MemberType Definition ---- ---------- ---------- Equals Method bool Equals(System.Object obj) GetHashCode Method int GetHashCode() GetType Method type GetType() ToString Method string ToString() Height NoteProperty System.Int32 Height=73 Name NoteProperty System.String Name=Michael
As you can see, the TypeName is "System.Management.Automation.PSCustomObject" and the new properties "Name" and "Height" are listed. The object type will be relevant to whatever object is piped in to Get-Member.
Get-PSDrive
Gets the Windows PowerShell drives in the current session.
Example:
# Displays details about the local disk C. Get-PSDrive C
Random fact:Try this: (Get-PSDrive)[0].Name <# Returns the name of the first object. #>Try this: (Get-PSDrive)[0].GetType() <# Returns the type of the first object. #>Set-LocationSets the current working location to a specified location.Example:# Changes the location to the registry hive HKEY_LOCAL_MACHINE. The colon is required. Set-Location HKLM:PS C:\> Set-Location HKLM: PS HKLM:\> Set-Location C: PS C:\> Set-Location Alias: PS Alias:\> dir | more CommandType Name ModuleName ----------- ---- ---------- Alias % -> ForEach-Object Alias ? -> Where-Object Alias ac -> Add-Content Alias asnp -> Add-PSSnapin Alias cat -> Get-Content Alias cd -> Set-Location Alias chdir -> Set-Location Alias clc -> Clear-Content Alias clear -> Clear-Host Alias clhy -> Clear-History Alias cli -> Clear-ItemAs you can see in the image above, I changed to the registry, then the C drive, then to Alias. In all of these locations, you can run the standard commands such as dir, ls, cd and so on. In the image you can also see that cd is an alias for Set-Location.Below are some command aliases common in other environments.
Command Aliases Copy-Item cpi, cp, copy ForEach-Object foreach, % Get-ChildItem dir, ls Get-Command gcm Get-Content gc, type, cat Get-Help help Get-Location gl, pwd Move-Item mi, mv, move Rename-Item rni, ren Set-Location cd, chdir Where-Object where, ? Remove-Item ri, rd, del, rm, rmdir Random fact:To count the number of items return, use Measure-Object. Use additional switch parameters such as -Sum and -Average.Try this: Get-Process | Measure-Object <# Returns a table with the results of Measure-Object. #>Try this: (Get-Process | Measure-Object).Count <# Returns the count value. #>Get-ContentGets the content of the item at the specified location.Example:# Reads the entire contents of the file. Get-Content -Path C:\log.txtAdd-ContentAdds content to the specified items, such as adding words to a file.Example:# Appends the text to the file log.txt. Add-Content -Path C:\log.txt -Value "The quick brown fox jumps over the lazy dog."Out-FileSends output to a file.Example:# The first command takes a snapshot of all the running processes. # The list passed through pipeline to Out-File which is then written to log.txt. Get-Process | Out-File -FilePath C:\log.txtWrite-HostWrites customized output to a host. The information is not kept in the pipeline.Example:# The text is written to the console window. Write-Host "This text is written to the host, such as the console window."Write-OutputSends the specified objects to the next command in the pipeline. If the command is the last command in the pipeline, the objects are displayed in the console.Example:# The snapshot of running processes is saved into the variable p. The variable p is then written to the console window. $p = Get-Process; Write-Output -InputObject $pWrite-VerboseThe text is written to the verbose message stream. This is commonly used in PowerShell scripts.New-ItemExample:# The text is written to the verbose stream. If the switch -Verbose is used, the text will be written to the console window. Write-Verbose -Message "The quick brown fox jumps over the lazy dog."
Creates a new item. The item can be a new registry key, file, directory, etc. The type of item created depends on which provider you are connected to.Example:# A new file is created with the specified text. New-Item -Path C:\ -Name log.txt -ItemType "file" New-Item -Path C:\log.txt -ItemType "file" -Value "The quick brown fox jumps over the lazy dog."
