Rediger

Del via

Chapter 2 - The Help system

  • Artikel

In an experiment designed to assess proficiency in PowerShell, two distinct groups of IT professionals — beginners and experts — were first given a written examination without access to a computer. Surprisingly, the test scores indicated comparable skills across both groups. A subsequent test was then administered, mirroring the first but with one key difference: participants had access to an offline computer equipped with PowerShell. The results revealed a significant skills gap between the two groups this time.

What factors contributed to the outcomes observed between the two assessments?

Experts don't always know the answers, but they know how to figure out the answers.

The outcomes observed in the results of the two tests were because experts don't memorize thousands of PowerShell commands. Instead, they excel at using the Help system within PowerShell, enabling them to discover and learn how to use commands when necessary.

Becoming proficient with the Help system is the key to success with PowerShell.

I heard Jeffrey Snover, the creator of PowerShell, share a similar story on multiple occasions.

Discoverability

Compiled commands in PowerShell are known as cmdlets, pronounced as "command-let", not "CMD-let". The naming convention for cmdlets follows a singular Verb-Noun format to make them easily discoverable. For instance, Get-Process is the cmdlet to determine what processes are running, and Get-Service is the cmdlet to retrieve a list of services. Functions, also known as script cmdlets, and aliases are other types of PowerShell commands that are discussed later in this book. The term "PowerShell command" describes any command in PowerShell, regardless of whether it's a cmdlet, function, or alias.

You can also run operating system native commands from PowerShell, such as traditional command-line programs like ping.exe and ipconfig.exe.

The three core cmdlets in PowerShell

  • Get-Help
  • Get-Command
  • Get-Member (covered in chapter 3)

I'm often asked: "How do you figure out what the commands are in PowerShell?". Both Get-Help and Get-Command are invaluable resources for discovering and understanding commands in PowerShell.

Get-Help

The first thing you need to know about the Help system in PowerShell is how to use the Get-Help cmdlet.

Get-Help is a multipurpose command that helps you learn how to use commands once you find them. You can also use Get-Help to locate commands, but in a different and more indirect way when compared to Get-Command.

When using Get-Help to locate commands, it initially performs a wildcard search for command names based on your input. If that doesn't find any matches, it conducts a comprehensive full-text search across all PowerShell help articles on your system. If that also fails to find any results, it returns an error.

Here's how to use Get-Help to view the help content for the Get-Help cmdlet.

Get-Help -Name Get-Help

Beginning with PowerShell version 3.0, the help content doesn't ship preinstalled with the operating system. When you run Get-Help for the first time, a message asks if you want to download the PowerShell help files to your computer.

Answering Yes by pressing Y executes the Update-Help cmdlet, downloading the help content.

Do you want to run Update-Help?
The Update-Help cmdlet downloads the most current Help files for Windows
PowerShell modules, and installs them on your computer. For more information
about the Update-Help cmdlet, see
https:/go.microsoft.com/fwlink/?LinkId=210614.
[Y] Yes  [N] No  [S] Suspend  [?] Help (default is "Y"):

If you don't receive this message, run Update-Help from an elevated PowerShell session running as an administrator.

Once the update is complete, the help article is displayed.

Take a moment to run the example on your computer, review the output, and observe how the help system organizes the information.

  • NAME
  • SYNOPSIS
  • SYNTAX
  • DESCRIPTION
  • RELATED LINKS
  • REMARKS

As you review the output, keep in mind that help articles often contain a vast amount of information, and what you see by default isn't the entire help article.

Parameters

When you run a command in PowerShell, you might need to provide additional information or input to the command. Parameters allow you to specify options and arguments that change the behavior of a command. The SYNTAX section of each help article outlines the available parameters for the command.

Get-Help has several parameters that you can specify to return the entire help article or a subset for a command. To view all the available parameters for Get-Help, see the SYNTAX section of its help article, as shown in the following example.

...
SYNTAX
    Get-Help [[-Name] <System.String>] [-Category {Alias | Cmdlet | Provider
    | General | FAQ | Glossary | HelpFile | ScriptCommand | Function |
    Filter | ExternalScript | All | DefaultHelp | Workflow | DscResource |
    Class | Configuration}] [-Component <System.String[]>] [-Full]
    [-Functionality <System.String[]>] [-Path <System.String>] [-Role
    <System.String[]>] [<CommonParameters>]

    Get-Help [[-Name] <System.String>] [-Category {Alias | Cmdlet | Provider
    | General | FAQ | Glossary | HelpFile | ScriptCommand | Function |
    Filter | ExternalScript | All | DefaultHelp | Workflow | DscResource |
    Class | Configuration}] [-Component <System.String[]>] -Detailed
    [-Functionality <System.String[]>] [-Path <System.String>] [-Role
    <System.String[]>] [<CommonParameters>]

    Get-Help [[-Name] <System.String>] [-Category {Alias | Cmdlet | Provider
    | General | FAQ | Glossary | HelpFile | ScriptCommand | Function |
    Filter | ExternalScript | All | DefaultHelp | Workflow | DscResource |
    Class | Configuration}] [-Component <System.String[]>] -Examples
    [-Functionality <System.String[]>] [-Path <System.String>] [-Role
    <System.String[]>] [<CommonParameters>]

    Get-Help [[-Name] <System.String>] [-Category {Alias | Cmdlet | Provider
    | General | FAQ | Glossary | HelpFile | ScriptCommand | Function |
    Filter | ExternalScript | All | DefaultHelp | Workflow | DscResource |
    Class | Configuration}] [-Component <System.String[]>] [-Functionality
    <System.String[]>] -Online [-Path <System.String>] [-Role
    <System.String[]>] [<CommonParameters>]

    Get-Help [[-Name] <System.String>] [-Category {Alias | Cmdlet | Provider
    | General | FAQ | Glossary | HelpFile | ScriptCommand | Function |
    Filter | ExternalScript | All | DefaultHelp | Workflow | DscResource |
    Class | Configuration}] [-Component <System.String[]>] [-Functionality
    <System.String[]>] -Parameter <System.String> [-Path <System.String>]
    [-Role <System.String[]>] [<CommonParameters>]

    Get-Help [[-Name] <System.String>] [-Category {Alias | Cmdlet | Provider
    | General | FAQ | Glossary | HelpFile | ScriptCommand | Function |
    Filter | ExternalScript | All | DefaultHelp | Workflow | DscResource |
    Class | Configuration}] [-Component <System.String[]>] [-Functionality
    <System.String[]>] [-Path <System.String>] [-Role <System.String[]>]
    -ShowWindow [<CommonParameters>]
...

Parameter sets

When you review the SYNTAX section for Get-Help, notice that the information appears to be repeated six times. Each of those blocks is an individual parameter set, indicating the Get-Help cmdlet features six distinct sets of parameters. A closer look reveals each parameter set contains at least one unique parameter, making it different from the others.

Parameter sets are mutually exclusive. Once you specify a unique parameter that only exists in one parameter set, PowerShell limits you to using the parameters contained within that parameter set. For instance, you can't use the Full and Detailed parameters of Get-Help together because they belong to different parameter sets.

Each of the following parameters belongs to a different parameter set for the Get-Help cmdlet.

  • Full
  • Detailed
  • Examples
  • Online
  • Parameter
  • ShowWindow

The command syntax

If you're new to PowerShell, comprehending the cryptic information — characterized by square and angle brackets — in the SYNTAX section might seem overwhelming. However, learning these syntax elements is essential to becoming proficient with PowerShell. The more frequently you use the PowerShell Help system, the easier it becomes to remember all the nuances.

View the syntax of the Get-EventLog cmdlet.

Get-Help Get-EventLog

The following output shows the relevant portion of the help article.

...
SYNTAX
    Get-EventLog [-LogName] <System.String> [[-InstanceId]
    <System.Int64[]>] [-After <System.DateTime>] [-AsBaseObject] [-Before
    <System.DateTime>] [-ComputerName <System.String[]>] [-EntryType {Error
    | Information | FailureAudit | SuccessAudit | Warning}] [-Index
    <System.Int32[]>] [-Message <System.String>] [-Newest <System.Int32>]
    [-Source <System.String[]>] [-UserName <System.String[]>]
    [<CommonParameters>]

    Get-EventLog [-AsString] [-ComputerName <System.String[]>] [-List]
    [<CommonParameters>]
...

The syntax information includes pairs of square brackets ([]). Depending on their usage, these square brackets serve two different purposes.

  • Elements enclosed in square brackets are optional.
  • An empty set of square brackets following a datatype, such as <string[]>, indicates that the parameter can accept multiple values passed as an array or a collection object.

Positional parameters

Some cmdlets are designed to accept positional parameters. Positional parameters allow you to provide a value without specifying the name of the parameter. When using a parameter positionally, you must specify its value in the correct position on the command line. You can find the positional information for a parameter in the PARAMETERS section of a command's help article. When you explicitly specify parameter names, you can use the parameters in any order.

For the Get-EventLog cmdlet, the first parameter in the first parameter set is LogName. LogName is enclosed in square brackets, indicating it's a positional parameter.

Get-EventLog [-LogName] <System.String>

Since LogName is a positional parameter, you can specify it by either name or position. According to the angle brackets following the parameter name, the value for LogName must be a single string. The absence of square brackets enclosing both the parameter name and datatype indicates that LogName is a required parameter within this particular parameter set.

The second parameter in that parameter set is InstanceId. Both the parameter name and datatype are entirely enclosed in square brackets, signifying that InstanceId is an optional parameter.

[[-InstanceId] <System.Int64[]>]

Furthermore, InstanceId has its own pair of square brackets, indicating that it's a positional parameter similar to the LogName parameter. Following the datatype, an empty set of square brackets implies that InstanceId can accept multiple values.

Switch parameters

A parameter that doesn't require a value is called a switch parameter. You can easily identify switch parameters because there's no datatype following the parameter name. When you specify a switch parameter, its value is true. When you don't specify a switch parameter, its value is false.

The second parameter set includes a List parameter, which is a switch parameter. When you specify the List parameter, it returns a list of event logs on the local computer.

[-List]

A simplified approach to syntax

There's a more user-friendly method to obtain the same information as the cryptic command syntax for some commands, except in plain English. PowerShell returns the complete help article when using Get-Help with the Full parameter, making it easier to understand a command's usage.

Get-Help -Name Get-Help -Full

Take a moment to run the example on your computer, review the output, and observe how the help system organizes the information.

  • NAME
  • SYNOPSIS
  • SYNTAX
  • DESCRIPTION
  • PARAMETERS
  • INPUTS
  • OUTPUTS
  • NOTES
  • EXAMPLES
  • RELATED LINKS

By specifying the Full parameter with the Get-Help cmdlet, the output includes several extra sections. Among these sections, PARAMETERS often provides a detailed explanation for each parameter. However, the extent of this information varies depending on the specific command you're investigating.

...
    -Detailed <System.Management.Automation.SwitchParameter>
        Adds parameter descriptions and examples to the basic help display.
        This parameter is effective only when the help files are installed
        on the computer. It has no effect on displays of conceptual ( About_
        ) help.

        Required?                    true
        Position?                    named
        Default value                False
        Accept pipeline input?       False
        Accept wildcard characters?  false

    -Examples <System.Management.Automation.SwitchParameter>
        Displays only the name, synopsis, and examples. This parameter is
        effective only when the help files are installed on the computer. It
        has no effect on displays of conceptual ( About_ ) help.

        Required?                    true
        Position?                    named
        Default value                False
        Accept pipeline input?       False
        Accept wildcard characters?  false

    -Full <System.Management.Automation.SwitchParameter>
        Displays the entire help article for a cmdlet. Full includes
        parameter descriptions and attributes, examples, input and output
        object types, and additional notes.

        This parameter is effective only when the help files are installed
        on the computer. It has no effect on displays of conceptual ( About_
        ) help.

        Required?                    false
        Position?                    named
        Default value                False
        Accept pipeline input?       False
        Accept wildcard characters?  false
...

When you ran the previous command to display the help for the Get-Help command, you probably noticed the output scrolled by too quickly to read it.

If you're using the PowerShell console, Windows Terminal, or VS Code and need to view a help article, the help function can be useful. It pipes the output of Get-Help to more.com, displaying one page of help content at a time. I recommend using the help function instead of the Get-Help cmdlet because it provides a better user experience and it's less to type.

Note

The ISE doesn't support using more.com, so running help works the same way as Get-Help.

Run each of the following commands in PowerShell on your computer.

Get-Help -Name Get-Help -Full
help -Name Get-Help -Full
help Get-Help -Full

Did you observe any variations in the output when you ran the previous commands?

In the previous example, the first line uses the Get-Help cmdlet, the second uses the help function, and the third line omits the Name parameter while using the help function. Since Name is a positional parameter, the third example takes advantage of its position instead of explicitly stating the parameter's name.

The difference is that the last two commands display their output one page at a time. When using the help function, press the Spacebar to display the next page of content or Q to quit. If you need to terminate any command running interactively in PowerShell, press Ctrl+C.

To quickly find information about a specific parameter, use the Parameter parameter. This approach returns content containing only the parameter-specific information, rather than the entire help article. This is the easiest way to find information about a specific parameter.

The following example uses the help function with the Parameter parameter to return information from the help article for the Name parameter of Get-Help.

help Get-Help -Parameter Name

The help information shows that the Name parameter is positional and must be specified in the first position (position zero) when used positionally.

-Name <System.String>
    Gets help about the specified command or concept. Enter the name of a
    cmdlet, function, provider, script, or workflow, such as `Get-Member`,
    a conceptual article name, such as `about_Objects`, or an alias, such
    as `ls`. Wildcard characters are permitted in cmdlet and provider
    names, but you can't use wildcard characters to find the names of
    function help and script help articles.

    To get help for a script that isn't located in a path that's listed in
    the `$env:Path` environment variable, type the script's path and file
    name.

    If you enter the exact name of a help article, `Get-Help` displays the
    article contents.

    If you enter a word or word pattern that appears in several help
    article titles, `Get-Help` displays a list of the matching titles.

    If you enter any text that doesn't match any help article titles,
    `Get-Help` displays a list of articles that include that text in their
    contents.

    The names of conceptual articles, such as `about_Objects`, must be
    entered in English, even in non-English versions of PowerShell.

    Required?                    false
    Position?                    0
    Default value                None
    Accept pipeline input?       True (ByPropertyName)
    Accept wildcard characters?  true

The Name parameter expects a string value as identified by the <String> datatype next to the parameter name.

There are several other parameters you can specify with Get-Help to return a subset of a help article. To see how they work, run the following commands on your computer.

Get-Help -Name Get-Command -Full
Get-Help -Name Get-Command -Detailed
Get-Help -Name Get-Command -Examples
Get-Help -Name Get-Command -Online
Get-Help -Name Get-Command -Parameter Noun
Get-Help -Name Get-Command -ShowWindow

I typically use help <command name> with the Full or Online parameter. If you only have an interest in the examples, use the Examples parameter. If you only have an interest in a specific parameter, use the Parameter parameter.

When you use the ShowWindow parameter, it displays the help content in a separate searchable window. You can move that window to a different monitor if you have multiple monitors. However, the ShowWindow parameter has a known bug that might prevent it from displaying the entire help article. The ShowWindow parameter also requires an operating system with a Graphical User Interface (GUI). It returns an error when you attempt to use it on Windows Server Core.

If you have internet access, you can use the Online parameter instead. The Online parameter opens the help article in your default web browser. The online content is the most up-to-date content. The browser allows you to search the help content and view other related help articles.

Note

The Online parameter isn't supported for About articles.

help Get-Command -Online

Finding commands with Get-Help

To find commands with Get-Help, specify a search term surrounded by asterisk (*) wildcard characters for the value of the Name parameter. The following example uses the Name parameter positionally.

help *process*

Name                              Category  Module                    Synops
----                              --------  ------                    ------
Enter-PSHostProcess               Cmdlet    Microsoft.PowerShell.Core Con...
Exit-PSHostProcess                Cmdlet    Microsoft.PowerShell.Core Clo...
Get-PSHostProcessInfo             Cmdlet    Microsoft.PowerShell.Core Get...
Debug-Process                     Cmdlet    Microsoft.PowerShell.M... Deb...
Get-Process                       Cmdlet    Microsoft.PowerShell.M... Get...
Start-Process                     Cmdlet    Microsoft.PowerShell.M... Sta...
Stop-Process                      Cmdlet    Microsoft.PowerShell.M... Sto...
Wait-Process                      Cmdlet    Microsoft.PowerShell.M... Wai...
Invoke-LapsPolicyProcessing       Cmdlet    LAPS                      Inv...
ConvertTo-ProcessMitigationPolicy Cmdlet    ProcessMitigations        Con...
Get-ProcessMitigation             Cmdlet    ProcessMitigations        Get...
Set-ProcessMitigation             Cmdlet    ProcessMitigations        Set...

In this scenario, you aren't required to add the * wildcard characters. If Get-Help can't find a command matching the value you provided, it does a full-text search for that value. The following example produces the same results as specifying the * wildcard character on each end of process.

help process

When you specify a wildcard character within the value, Get-Help only searches for commands that match the pattern you provided. It doesn't perform a full-text search. The following command doesn't return any results.

help pr*cess

PowerShell generates an error if you specify a value that begins with a dash without enclosing it in quotes because it interprets it as a parameter name. No such parameter name exists for the Get-Help cmdlet.

help -process

If you're attempting to search for commands that end with -process, you must add an * to the beginning of the value.

help *-process

When you search for PowerShell commands with Get-Help, it's better to be vague rather than too specific.

When you searched for process earlier, the results only returned commands that included process in their name. But if you search for processes, it doesn't find any matches for command names. As previously stated, when help doesn't find any matches, it performs a comprehensive full-text search of every help article on your system and returns those results. This type of search often produces more results than expected, including information not relevant to you.

help processes

Name                              Category  Module                    Synops
----                              --------  ------                    ------
Disconnect-PSSession              Cmdlet    Microsoft.PowerShell.Core Dis...
Enter-PSHostProcess               Cmdlet    Microsoft.PowerShell.Core Con...
ForEach-Object                    Cmdlet    Microsoft.PowerShell.Core Per...
Get-PSHostProcessInfo             Cmdlet    Microsoft.PowerShell.Core Get...
Get-PSSessionConfiguration        Cmdlet    Microsoft.PowerShell.Core Get...
New-PSSessionOption               Cmdlet    Microsoft.PowerShell.Core Cre...
New-PSTransportOption             Cmdlet    Microsoft.PowerShell.Core Cre...
Out-Host                          Cmdlet    Microsoft.PowerShell.Core Sen...
Start-Job                         Cmdlet    Microsoft.PowerShell.Core Sta...
Where-Object                      Cmdlet    Microsoft.PowerShell.Core Sel...
Debug-Process                     Cmdlet    Microsoft.PowerShell.M... Deb...
Get-Process                       Cmdlet    Microsoft.PowerShell.M... Get...
Get-WmiObject                     Cmdlet    Microsoft.PowerShell.M... Get...
Start-Process                     Cmdlet    Microsoft.PowerShell.M... Sta...
Stop-Process                      Cmdlet    Microsoft.PowerShell.M... Sto...
Wait-Process                      Cmdlet    Microsoft.PowerShell.M... Wai...
Clear-Variable                    Cmdlet    Microsoft.PowerShell.U... Del...
Convert-String                    Cmdlet    Microsoft.PowerShell.U... For...
ConvertFrom-Csv                   Cmdlet    Microsoft.PowerShell.U... Con...
ConvertFrom-Json                  Cmdlet    Microsoft.PowerShell.U... Con...
ConvertTo-Html                    Cmdlet    Microsoft.PowerShell.U... Con...
ConvertTo-Xml                     Cmdlet    Microsoft.PowerShell.U... Cre...
Debug-Runspace                    Cmdlet    Microsoft.PowerShell.U... Sta...
Export-Csv                        Cmdlet    Microsoft.PowerShell.U... Con...
Export-FormatData                 Cmdlet    Microsoft.PowerShell.U... Sav...
Format-List                       Cmdlet    Microsoft.PowerShell.U... For...
Format-Table                      Cmdlet    Microsoft.PowerShell.U... For...
Get-Unique                        Cmdlet    Microsoft.PowerShell.U... Ret...
Group-Object                      Cmdlet    Microsoft.PowerShell.U... Gro...
Import-Clixml                     Cmdlet    Microsoft.PowerShell.U... Imp...
Import-Csv                        Cmdlet    Microsoft.PowerShell.U... Cre...
Measure-Object                    Cmdlet    Microsoft.PowerShell.U... Cal...
Out-File                          Cmdlet    Microsoft.PowerShell.U... Sen...
Out-GridView                      Cmdlet    Microsoft.PowerShell.U... Sen...
Select-Object                     Cmdlet    Microsoft.PowerShell.U... Sel...
Set-Variable                      Cmdlet    Microsoft.PowerShell.U... Set...
Sort-Object                       Cmdlet    Microsoft.PowerShell.U... Sor...
Tee-Object                        Cmdlet    Microsoft.PowerShell.U... Sav...
Trace-Command                     Cmdlet    Microsoft.PowerShell.U... Con...
Write-Information                 Cmdlet    Microsoft.PowerShell.U... Spe...
Export-BinaryMiLog                Cmdlet    CimCmdlets                Cre...
Get-CimAssociatedInstance         Cmdlet    CimCmdlets                Ret...
Get-CimInstance                   Cmdlet    CimCmdlets                Get...
Import-BinaryMiLog                Cmdlet    CimCmdlets                Use...
Invoke-CimMethod                  Cmdlet    CimCmdlets                Inv...
New-CimInstance                   Cmdlet    CimCmdlets                Cre...
Remove-CimInstance                Cmdlet    CimCmdlets                Rem...
Set-CimInstance                   Cmdlet    CimCmdlets                Mod...
Compress-Archive                  Function  Microsoft.PowerShell.A... Cre...
Get-Counter                       Cmdlet    Microsoft.PowerShell.D... Get...
Invoke-WSManAction                Cmdlet    Microsoft.WSMan.Manage... Inv...
Remove-WSManInstance              Cmdlet    Microsoft.WSMan.Manage... Del...
Get-WSManInstance                 Cmdlet    Microsoft.WSMan.Manage... Dis...
New-WSManInstance                 Cmdlet    Microsoft.WSMan.Manage... Cre...
Set-WSManInstance                 Cmdlet    Microsoft.WSMan.Manage... Mod...
about_Arithmetic_Operators        HelpFile
about_Arrays                      HelpFile
about_Environment_Variables       HelpFile
about_Execution_Policies          HelpFile
about_Functions                   HelpFile
about_Jobs                        HelpFile
about_Logging                     HelpFile
about_Methods                     HelpFile
about_Objects                     HelpFile
about_Pipelines                   HelpFile
about_Preference_Variables        HelpFile
about_Remote                      HelpFile
about_Remote_Jobs                 HelpFile
about_Session_Configuration_Files HelpFile
about_Simplified_Syntax           HelpFile
about_Switch                      HelpFile
about_Variables                   HelpFile
about_Variable_Provider           HelpFile
about_Windows_Powershell_5.1      HelpFile
about_WQL                         HelpFile
about_WS-Management_Cmdlets       HelpFile
about_Foreach-Parallel            HelpFile
about_Parallel                    HelpFile
about_Sequence                    HelpFile

When you searched for process, it returned 12 results. However, when searching for processes, it produced 78 results. If your search only finds one match, Get-Help displays the help content instead of listing the search results.

help *hotfix*

NAME
    Get-HotFix

SYNOPSIS
    Gets the hotfixes that are installed on local or remote computers.


SYNTAX
    Get-HotFix [-ComputerName <System.String[]>] [-Credential
    <System.Management.Automation.PSCredential>] [-Description
    <System.String[]>] [<CommonParameters>]

    Get-HotFix [[-Id] <System.String[]>] [-ComputerName <System.String[]>]
    [-Credential <System.Management.Automation.PSCredential>]
    [<CommonParameters>]


DESCRIPTION
    > This cmdlet is only available on the Windows platform. The
    `Get-Hotfix` cmdlet uses the Win32_QuickFixEngineering WMI class to
    list hotfixes that are installed on the local computer or specified
    remote computers.


RELATED LINKS
    Online Version: https://learn.microsoft.com/powershell/module/microsoft.
    powershell.management/get-hotfix?view=powershell-5.1&WT.mc_id=ps-gethelp
    about_Arrays
    Add-Content
    Get-ComputerRestorePoint
    Get-Credential
    Win32_QuickFixEngineering class

REMARKS
    To see the examples, type: "get-help Get-HotFix -examples".
    For more information, type: "get-help Get-HotFix -detailed".
    For technical information, type: "get-help Get-HotFix -full".
    For online help, type: "get-help Get-HotFix -online"

You can also find commands that lack help articles with Get-Help, although this capability isn't commonly known. The more function is one of the commands that doesn't have a help article. To confirm that you can find commands with Get-Help that don't include help articles, use the help function to find more.

help *more*

The search only found one match, so it returned the basic syntax information you see when a command doesn't have a help article.

NAME
    more

SYNTAX
    more [[-paths] <string[]>]

ALIASES
    None

REMARKS
    None

The PowerShell help system also contains conceptual About help articles. You must update the help content on your system to get the About articles. For more information, see the Updating help section of this chapter.

Use the following command to return a list of all About help articles on your system.

help About_*

When you limit the results to one About help article, Get-Help displays the content of that article.

help about_Updatable_Help

Updating help

Earlier in this chapter, you updated the PowerShell help articles on your computer the first time you ran the Get-Help cmdlet. You should periodically run the Update-Help cmdlet on your computer to obtain any updates to the help content.

Important

In Windows PowerShell 5.1, you must run Update-Help as an administrator in an elevated PowerShell session.

In the following example, Update-Help downloads the PowerShell help content for all modules installed on your computer. You should use the Force parameter to ensure that you download the latest version of the help content.

Update-Help -Force

As shown in the following results, a module returned an error. Errors aren't uncommon and usually occur when the module's author doesn't configure updatable help correctly.

Update-Help : Failed to update Help for the module(s) 'BitsTransfer' with UI
culture(s) {en-US} : Unable to retrieve the HelpInfo XML file for UI culture
en-US. Make sure the HelpInfoUri property in the module manifest is valid or
check your network connection and then try the command again.
At line:1 char:1
+ Update-Help
+ ~~~~~~~~~~~
    + CategoryInfo          : ResourceUnavailable: (:) [Update-Help], Except
   ion
    + FullyQualifiedErrorId : UnableToRetrieveHelpInfoXml,Microsoft.PowerShe
   ll.Commands.UpdateHelpCommand

Update-Help requires internet access to download the help content. If your computer doesn't have internet access, use the Save-Help cmdlet on a computer with internet access to download and save the updated help content. Then, use the SourcePath parameter of Update-Help to specify the location of the saved updated help content.

Get-Command

Get-Command is another multipurpose command that helps you find commands. When you run Get-Command without any parameters, it returns a list of all PowerShell commands on your system. You can also use Get-Command to get command syntax similar to Get-Help.

How do you determine the syntax for Get-Command? You could use Get-Help to display the help article for Get-Command, as shown in the Get-Help section of this chapter. You can also use Get-Command with the Syntax parameter to view the syntax for any command. This shortcut helps you quickly determine how to use a command without navigating through its help content.

Get-Command -Name Get-Command -Syntax

Using Get-Command with the Syntax parameter provides a more concise view of the syntax that shows the parameters and their value types, without listing the specific allowable values like Get-Help shows.

Get-Command [[-ArgumentList] <Object[]>] [-Verb <string[]>]
[-Noun <string[]>] [-Module <string[]>]
[-FullyQualifiedModule <ModuleSpecification[]>] [-TotalCount <int>]
[-Syntax] [-ShowCommandInfo] [-All] [-ListImported]
[-ParameterName <string[]>] [-ParameterType <PSTypeName[]>]
[<CommonParameters>]

Get-Command [[-Name] <string[]>] [[-ArgumentList] <Object[]>]
[-Module <string[]>] [-FullyQualifiedModule <ModuleSpecification[]>]
[-CommandType <CommandTypes>] [-TotalCount <int>] [-Syntax]
[-ShowCommandInfo] [-All] [-ListImported] [-ParameterName <string[]>]
[-ParameterType <PSTypeName[]>] [<CommonParameters>]

If you need more detailed information about how to use a command, use Get-Help.

help Get-Command -Full

The SYNTAX section of Get-Help provides a more user-friendly display by expanding enumerated values for parameters. It shows you the actual values you can use, making it easier to understand the available options.

...
    Get-Command [[-Name] <System.String[]>] [[-ArgumentList]
    <System.Object[]>] [-All] [-CommandType {Alias | Function | Filter |
    Cmdlet | ExternalScript | Application | Script | Workflow |
    Configuration | All}] [-FullyQualifiedModule
    <Microsoft.PowerShell.Commands.ModuleSpecification[]>] [-ListImported]
    [-Module <System.String[]>] [-ParameterName <System.String[]>]
    [-ParameterType <System.Management.Automation.PSTypeName[]>]
    [-ShowCommandInfo] [-Syntax] [-TotalCount <System.Int32>]
    [<CommonParameters>]

    Get-Command [[-ArgumentList] <System.Object[]>] [-All]
    [-FullyQualifiedModule
    <Microsoft.PowerShell.Commands.ModuleSpecification[]>] [-ListImported]
    [-Module <System.String[]>] [-Noun <System.String[]>] [-ParameterName
    <System.String[]>] [-ParameterType
    <System.Management.Automation.PSTypeName[]>] [-ShowCommandInfo]
    [-Syntax] [-TotalCount <System.Int32>] [-Verb <System.String[]>]
    [<CommonParameters>]
...

The PARAMETERS section of the help for Get-Command reveals that the Name, Noun, and Verb parameters accept wildcard characters.

...
    -Name <System.String[]>
        Specifies an array of names. This cmdlet gets only commands that
        have the specified name. Enter a name or name pattern. Wildcard
        characters are permitted.

        To get commands that have the same name, use the All parameter. When
        two commands have the same name, by default, `Get-Command` gets the
        command that runs when you type the command name.

        Required?                    false
        Position?                    0
        Default value                None
        Accept pipeline input?       True (ByPropertyName, ByValue)
        Accept wildcard characters?  true

    -Noun <System.String[]>
        Specifies an array of command nouns. This cmdlet gets commands,
        which include cmdlets, functions, and aliases, that have names that
        include the specified noun. Enter one or more nouns or noun
        patterns. Wildcard characters are permitted.

        Required?                    false
        Position?                    named
        Default value                None
        Accept pipeline input?       True (ByPropertyName)
        Accept wildcard characters?  true
    -Verb <System.String[]>
        Specifies an array of command verbs. This cmdlet gets commands,
        which include cmdlets, functions, and aliases, that have names that
        include the specified verb. Enter one or more verbs or verb
        patterns. Wildcard characters are permitted.

        Required?                    false
        Position?                    named
        Default value                None
        Accept pipeline input?       True (ByPropertyName)
        Accept wildcard characters?  true
...

The following example uses the * wildcard character with the value for the Name parameter of Get-Command.

Get-Command -Name *service*

When you use wildcard characters with the Name parameter of Get-Command, it returns PowerShell commands and native commands, as shown in the following results.


CommandType     Name                                               Version
-----------     ----                                               -------
Function        Get-NetFirewallServiceFilter                       2.0.0.0
Function        Set-NetFirewallServiceFilter                       2.0.0.0
Cmdlet          Get-Service                                        3.1.0.0
Cmdlet          New-Service                                        3.1.0.0
Cmdlet          New-WebServiceProxy                                3.1.0.0
Cmdlet          Restart-Service                                    3.1.0.0
Cmdlet          Resume-Service                                     3.1.0.0
Cmdlet          Set-Service                                        3.1.0.0
Cmdlet          Start-Service                                      3.1.0.0
Cmdlet          Stop-Service                                       3.1.0.0
Cmdlet          Suspend-Service                                    3.1.0.0
Application     SecurityHealthService.exe                          10.0.2...
Application     SensorDataService.exe                              10.0.2...
Application     services.exe                                       10.0.2...
Application     services.msc                                       0.0.0.0
Application     TieringEngineService.exe                           10.0.2...
Application     Windows.WARP.JITService.exe                        10.0.2...

You can limit the results of Get-Command to PowerShell commands using the CommandType parameter.

Get-Command -Name *service* -CommandType Cmdlet, Function, Alias, Script

Another option might be to use either the Verb or Noun parameter or both since only PowerShell commands have verbs and nouns.

The following example uses Get-Command to find commands on your computer that work with processes. Use the Noun parameter and specify Process as its value.

Get-Command -Noun Process

CommandType     Name                                               Version
-----------     ----                                               -------
Cmdlet          Debug-Process                                      3.1.0.0
Cmdlet          Get-Process                                        3.1.0.0
Cmdlet          Start-Process                                      3.1.0.0
Cmdlet          Stop-Process                                       3.1.0.0
Cmdlet          Wait-Process                                       3.1.0.0

Summary

In this chapter, you learned how to find commands with Get-Help and Get-Command. You also learned how to use the help system to understand how to use commands once you find them. In addition, you learned how to update the help system on your computer when new help content is available.

Review

  1. Is the DisplayName parameter of Get-Service positional?
  2. How many parameter sets does the Get-Process cmdlet have?
  3. What PowerShell commands exist for working with event logs?
  4. What's the PowerShell command for returning a list of PowerShell processes running on your computer?
  5. How do you update the PowerShell help content stored on your computer?

References

To learn more about the concepts covered in this chapter, read the following PowerShell help articles.

Next steps

In the next chapter, you'll learn about objects, properties, methods, and the Get-Member cmdlet.