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Professional
Windows PowerShell

Programming
Snap-ins, Cmdlets, Hosts, and Providers
Arul Kumaravel
Jon White
Michael Naixin Li
Scott Happell
Guohui Xie
Krishna C. Vutukuri
Wiley Publishing, Inc.
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Kumaravel ffirs.tex V1 - 01/09/2008 8:43pm Page i
Professional
Windows PowerShell

Programming
Preface xvii
Introduction xix
Chapter 1: Introduction to PowerShell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Chapter 2: Extending Windows PowerShell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Chapter 3: Understanding the Extended Type System . . . . . . . . . . . . . . . . . . . . . . 29
Chapter 4: Developing Cmdlets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Chapter 5: Providers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Chapter 6: Hosting the PowerShell Engine in Applications . . . . . . . . . . . . . . . . . 165
Chapter 7: Hosts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
Chapter 8: Formatting&Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
Appendix A: Cmdlet Verb Naming Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257

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debug.exe
from 64-bit Windows. As a member of the PowerShell team,
he wrote the language’s first production script, when he converted the team’s test harness from Perl to
PowerShell script in 2004. When he’s not working (or writing about work) he’s either sailing or playing
with fire in the backyard. You can contact him at
[email protected]
.
Michael Naixin Li is the Senior Test Lead working on the Windows PowerShell team and currently
oversees the testing of Windows PowerShell 2.0. Before Windows PowerShell, Michael worked on vari-
ous major projects at Microsoft, including the development of MSN 1.x and 2.x, quality management for
the COM Services component in Windows 2000, NetDocs Web Client Access, Web Services in Hailstorm,
and Software Licensing Service in Windows Vista. Before joining Microsoft, Michael was an assistant
professor at Shanghai University of Science and Technology (now called ShanghaiUniversity).Heholds
a Ph.D. in Computer Science from Colorado State University.
Scott Happell has been working as a software engineer and tester for 10 years. Three of those years have
been on the Windows PowerShell team, which was what brought him to Microsoft from New Jersey,
where he worked at an Internet startup that went belly-up. Scott recently left Microsoft to become a
recording engineer/rock star and is trying to find cool ways to use PowerShell to help him create music.
George Xie was a Senior Developer in the Windows PowerShell team for three years, mainly focusing
in the area of snap-in model and scripting language. Recently George joined Windows Mobile organi-
zation for the Mobile Device Management product. Before joining Microsoft, George worked for Siebel
Systems Inc. for several years.
Krishna Chythanya Vutukuri is a Software Developer working on the Windows PowerShell team. Before
Windows PowerShell, Krishna worked on various projects at Microsoft, which included the development
of Windows Presentation Foundation. Before joining Microsoft, Krishna held various product develop-
ment positions at Hewlett-Packard India Software Operations and Wipro Technologies. He holds a M.Sc
(Tech.) in Information Systems from Birla Institute of Technology and Science, Pilani, India.
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Credits

Tear Down the Barriers to Development 2
A Quick Tour of Windows PowerShell 3
Cmdlets 3
High-Level Architecture of Windows PowerShell 9
Host Application 9
Windows PowerShell Engine 10
Windows PowerShell Snap-ins 10
Summary 11
Chapter 2: Extending Windows PowerShell 13
Types of PowerShell Snap-ins 13
Creating a Standard PowerShell Snap-in 14
Writing a PowerShell Snap-in 14
Registering Your PowerShell Snap-in 17
Listing Available PowerShell Snap-ins 19
Loading a PowerShell Snap-in to a Running Shell 19
Removing a PowerShell Snap-in from a Running Shell 20
Unregistering a PowerShell Snap-in 20
Registering a PowerShell Snap-in without Implementing a Snap-in Clas 21
Saving Snap-in Configuration 22
Starting PowerShell with a Saved Snap-in Configuration 22
Using a Profile to Save a Snap-in Configuration 23
Creating a Custom PowerShell Snap-in 23
Writing a Custom PowerShell Snap-in 23
Using a Custom PowerShell Snap-in 25
Summary 27