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Get-Help: PowerShell’s Documentation Framework

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Get-Help for Get-Help!
Get-Help for Get-Help 🙂

Display documentation for PowerShell components using Get-Help.

This is the first post in the series PowerShell 1.0 – The First Cmdlets. In this post we will cover Get-Help , which was one of the Microsoft.PowerShell.Core  module cmdlets and a cmdlet we will use extensively in future posts. Note that though this cmdlet was first introduced in PowerShell 1.0, enhancements have been made through version releases and we will cover the latest features of the cmdlet.

Get-Help: What it is for

Get-Help  displays help documentation for PowerShell cmdlets and concepts. It is the method from within PowerShell that you can bring up details of how to use PowerShell components. This cmdlet will be a regular part of your daily PowerShell toolbox.

Examples: How to use it

Get documentation for a cmdlet

One of the most common ways you will use Get-Help  is to get documentation about how to use a specific cmdlet. You type Get-Help  followed by the cmdlet name you want documentation for, so an example would be Get-Help Get-Help . Run this from a PowerShell session to see the standard help displayed.

Specify level of documentation to display

There a few parameters to control the level of documentation to display, some being more verbose than others.

  • -examples  will show you the examples within the help file.
  • -detailed  will show a more complete documentation set, including examples as well as a breakdown of the Parameters.
  • -full  will show you everything included in -detailed as well as Input and Output information and general Notes.

Launch online documentation from docs.microsoft.com

One of my favorite new features is to use the -online  parameter to launch the help page for a given cmdlet or component that resides at docs.microsoft.com. The online help pages are well formatted and easy to navigate, so if you like to reference your documentation separate from where you are working or on a second screen (I personally do), this is a killer feature.

Get-Help Get-Help -online

See components with help available

Using Get-Help isn’t limited to cmdlets. There are multiple categories, including “About” topics (preceded with ‘about_’), functions, providers, and aliases. You can see what help options are available using wildcard searches or by specifying a category to filter:

# Wildcard search for anything beginning with about_ ("About" topics)
Get-Help -Name about_*

# Show Providers for which there is help information
Get-Help -Category Provider

Next Up: Get/Add/Remove-PSSnapin

In the next post of the series, we will cover the PSSnapin cmdlets, Get-PSSnapin , Add-PSSnapin , and Remove-PSSnapin .

Reference

Test PowerShell Variable for Null, Empty String, and White Space

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Learn the difference between a null, empty string, and white space value for a PowerShell variable and how to test for them.

PowerShell variables without “value”

More often than not, we create variables with the intent they will hold a value. We typically then choose to act upon that value. Therefore, if a variable doesn’t have value, this is something we would want to check against in our conditional logic flow.

[Read more…] about Test PowerShell Variable for Null, Empty String, and White Space

How to Make a PowerShell Progress Bar

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Roll your own PowerShell progress bar.
Roll your own PowerShell progress bar.

Some cmdlets have a progress bar built-in. Here’s how to make your own Powershell progress bar with the Write-Progress cmdlet.

What’s happening?

In my last post, I covered how to hide PowerShell progress bars you encounter with some built-in cmdlets. More often than not though, you probably want to keep these progress bars as they are typically there to give the script executor feedback that the script is indeed running, and how far along it is in step execution.

Microsoft has done a good job recognizing which cmdlets likely will have longer execution times (like Install-WindowsFeature), but what if you have a process that you know could take a while to complete? How can you give your user feedback that the script is actively working and to give an idea of how much work has been done, while also giving an impression of how much work is left to do?

[Read more…] about How to Make a PowerShell Progress Bar