This document provides an overview of PowerShell fundamentals that will be covered, including custom objects, advanced function parameters, building proper functions, the help system, pipelines, scope, and more. It does not cover PowerShell syntax or specific SharePoint cmdlets. The help system, pipelines, scope, custom objects, functions, parameter validation, verbose/debug output, and converting scripts to modules are discussed in more detail. Code examples are provided to demonstrate many of these concepts.

1. PowerShell Fundamentals
BY PAWEL MOZDZEN
1

2. PowerShell ISE
POWERSHELL FUNDAMENTALS 2
DEMOFinalProduct.ps1
FinalProductRun.ps1

3. What we will cover
POWERSHELL FUNDAMENTALS 3
 Custom Objects
 Advanced Parameters
 Steps for Building a Proper Function
 Help System
 Pipeline
 Scope
But not..
 PowerShell Syntax
 Specific SharePoint Cmdlets

4. Help System
 Update-Help
 Get-Help
 Get-Help Parameters
- Full
- Examples
- Detailed
- Online
- ShowWindow
 Get-Member
POWERSHELL FUNDAMENTALS 4
Examples
1. Get-Help Get-SPSite –Full
2. Get-Help Get-SP*
3. Get-Help Get-SPSite –Parameter Limit
Examples
1. Get-SPSite | Get-Member
2. Get-SPSite | Select Url, Owner | Get-Member

5. PowerShell ISE
POWERSHELL FUNDAMENTALS 5
DEMOHelp.ps1

6. Understanding Help Syntax
Get-Help New-SPSite
Syntax
New-SPSite [-AdministrationSiteType
<None | TenantAdministration>] [-AssignmentCollection <SPAssignmentCollection>] [-
CompatibilityLevel <Int32>] [-Confirm <SwitchParameter>] [-ContentDatabase
<SPContentDatabasePipeBind>] [-Description <String>] [-HostHeaderWebApplication
<SPWebApplicationPipeBind>] [-Language <UInt32>] [-Name <String>] [-
OverrideCompatibilityRestriction <SwitchParameter>] [-OwnerEmail <String>] [-QuotaTemplate
<SPQuotaTemplatePipeBind>] [-SecondaryEmail <String>] [-SecondaryOwnerAlias
<SPUserPipeBind>] [-SiteSubscription <SPSiteSubscriptionPipeBind>] [-Template
<SPWebTemplatePipeBind>] [-WhatIf <SwitchParameter>]
POWERSHELL FUNDAMENTALS 6
[-Url] <String>[-Url] <String> -OwnerAlias <SPUserPipeBind>-OwnerAlias <SPUserPipeBind>
[<CommonParameters>][<CommonParameters>]
Get-Help New-SPUser …[-PermissionLevel <String[]>] …..

7. Pipeline
POWERSHELL FUNDAMENTALS 7

8. Pipeline - the Old Way
POWERSHELL FUNDAMENTALS 8
Command I
StdOut StdIn StdErr
Command II
StdOut StdIn StdErr
Text

9. Working with Pipeline – PowerShell Way
POWERSHELL FUNDAMENTALS 9
Command I
Output Errors Warnings
Command II
-Param
OBJECT
Verbose Debug
-Param-Param
1
-Param
-Param-Param
…n
?  Pipeline Parameter Binding
 By Value
 By Property Name

10. Pipeline
POWERSHELL FUNDAMENTALS 10
DEMOPipeByValue.ps1
PipeByPropertyName.ps1

11. Scope
Global Scope - Runspace
POWERSHELL FUNDAMENTALS 11
Global Scope - Runspace
Function
Scope
Script Scope
Function
Scope
Script Scope
Script Scope
Function Scope
Compartmentalization of Scope

12.  General Rules
 Scoped elements exist only in scope they were created.
 Accessing non-existent element will result in reaching out to the parent scope.
 Scoped elements can be created with the same name as in the parent scope.
 When a scope is finished processing it is destroyed and removed from memory.
 Dot Sourcing
 Private variables
 Strict Mode
 Set-StrictMode -Off
 Set-StrictMode -Version [1,2,3,latest]
Scope
POWERSHELL FUNDAMENTALS 12

13. Scope
POWERSHELL FUNDAMENTALS 13
DEMOScopeRunScript.ps1
ScopeTempScript.ps1

14.  Benefits for turning script into a function
 Once loaded into memory it is available for later use: Dot-Sourcing, Import-Module
 Function has its own scope
 Multiple functions per script file.
 Provides better separation of concerns for complex tasks.
 Function Example
function Get-SiteColumnStats{
$spWeb = Get-spweb "http://sps-demo:5555/sites/acct"
$spFields = $spWeb.Fields
$spFields | Group-Object TypeAsString | Sort-Object Count -Descending
}
Get-SiteColumnStats
Functions
POWERSHELL FUNDAMENTALS 14

15.  Everything in PowerShell is an OBJECT
 Functions and scripts can return only one kind of thing.
 Use Custom Objects to consolidate information before returning it.
 To return a collection of data assign it to a property of the custom object.
 Techniques for creating custom objects:
 Using Hashtable
 Using Select-Object
 Using Add-Member
 Using Type Declaration
Custom Objects
POWERSHELL FUNDAMENTALS 15

16. Custom Objects – Creation Techniques
POWERSHELL FUNDAMENTALS 16
DEMOCustomObjects.ps1

17. Custom Objects - Real Life Example
POWERSHELL FUNDAMENTALS 17
DEMOExport-Audiences.ps1

18. Functions – Advanced Parameters
POWERSHELL FUNDAMENTALS 18
 Get-Help about_Functions_Advanced_Paramenters
 All PowerShell functions follow a verb dash
noun naming standard.
 Adds certain features to a function:
• Enables [Parameter()] decorator,
• Adds standard set of extra function
parameters such us –verbose, -debug
 Makes parameter required.
 Any default values will be ignored.
 Enables to accept values from pipeline.
 Accepts values of the same type.
 Only one such decorator for the same type.
 Enables to accept values from pipeline.
 Accepts values from passed in object’s
properties same name.
 First it will try to find a match By Value then
by Property Name
 BEGIN and END blocks execute only once.
 PROCESS block executes for each piped in
object
 Important to handle function calls where
values are passed in via parameter.
 Redundant if piped in.

19. Advanced Parameters - Real Life Example
POWERSHELL FUNDAMENTALS 19
DEMOExport-Audiences.ps1

20.  Defined as set of parameter decorators.
 Each validator defined as a separate decorator.
[ValidateCount(1,50)]
[ValidateLength(1,50)]
[ValidateScript({...})]
[ValidateSet[("One","Two","Three")]
[ValidatePattern("w+w+")]
[ValidateRange(1,5)]
Parameter Validation
POWERSHELL FUNDAMENTALS 20

21.  Validate against null or empty values:
[ValidateNotNull()]
[ValidateNotNullOrEmpty()]
 For mandatory parameters to allow null values:
[AllowNull()]
[AllowEmptyString()]
[AllowEmptyCollection()]
Parameter Validation – Cont’d.
POWERSHELL FUNDAMENTALS 21

22. Parameter Validation - Example
POWERSHELL FUNDAMENTALS 22

23.  Verbose Output: Write-Verbose
A way to check variables’ state in longer scripts
A way to comment script behavior documenting it
A way to notify about longer running processes
And the most important..
 Debug Output: Write-Debug
To let you know which line is currently processing
To pause the execution and let user check things
Verbose and Debug Output
POWERSHELL FUNDAMENTALS 23
a way to avoid using Write-Host

24.  Converting script to a module
 Accessing Module
 Use: Import-Module moduleFileName.psm1
 Place module in PowerShell searchable locations: $env:PSModulePath
Special considerations for saving modules in PowerShell locations:
 Always save your module within a folder of the same name.
 Use letters and numbers only.
 Exporting Module Members
Export-ModuleMember -Function <functionName>
Export-ModuleMember -Variable <variableName>
Example: Export-ModuleMember -Function *-*
Functions in Script Modules
POWERSHELL FUNDAMENTALS 24

25.  Start with defining a task.
 Build base command(s).
 Turn it into a function.
 Parameterize it.
 Test it calling in different ways.
 Add error handling if necessary.
 Add Verbose and Debug output.
 Turn it into a module.
Steps for Building a Proper Function
POWERSHELL FUNDAMENTALS 25

26. Steps for Building a Proper Function
POWERSHELL FUNDAMENTALS 26
DEMOFunctionBuildingSteps.ps1

27. PowerShell Fundamentals
QUESTIONS
27