This series is in four parts: This is part 2
- Part 1: Help, Syntax, Display and Files
- Part 2: Variables, Parameters, Properties, and Objects,
- Part 3: Collections, Hashtables, Arrays and Strings
- Part 4: Accessing, Handling and Writing Data
This is part of a multi-part series of PowerShell reference charts. Here you will find details about variables, parameters, properties, and objects, providing insight into the richness of the PowerShell programming language. Part 2 is rounded out with a few other vital bits on leveraging the PowerShell environment.
- Part 1
- Be sure to review part 1 first, though, which begins by showing you how to have PowerShell itself help you figure out what you need to do to accomplish a task, covering the help system as well as its handy command-line intellisense. It also examines locations, files, and paths (the basic currency of a shell); key syntactic constructs; and ways to cast your output in list, table, grid, or chart form.
- Part 2
- this article.
- Part 3
- covers the two fundamental data structures of PowerShell: the collection (array) and the hash table (dictionary), examining everything from creating, accessing, iterating, ordering, and selecting. Part 3 also covers converting between strings and arrays, and rounds out with techniques for searching, most commonly applicable to files (searching both directory structures as well as file contents).
- Part 4
- is your information source for a variety of input and output techniques: reading and writing files; writing the various output streams; file housekeeping operations; and various techniques related to CSV, JSON, database, network, and XML.
Each part of this series is available as both an online reference here at Simple-Talk.com, in a wide-form as well, and as a downloadable wallchart (from the link at the bottom of the article) in PDF format for those who prefer a printed copy near at hand. Please keep in mind though that this is a quick reference, not a tutorial. So while there are a few brief introductory remarks for each section, there is very little explanation for any given incantation. But do not let that scare you off-jump in and try things! You should find more than a few “aha!” moments ahead of you!
Notes on using the tables:
- A command will typically use full names of cmdlets but the examples will often use aliases for brevity. Example: Get-Help has aliases man and help. This has the side benefit of showing you both long and short names to invoke many commands.
- Most tables contain either 3 or 4 columns: a description of an action; the generic command syntax to perform that action; an example invocation of that command; and optionally an output column showing the result of that example where feasible.
- For clarity, embedded newlines (`n) and embedded return/newline combinations (`r`n) are highlighted as shown.
- Many actions in PowerShell can be performed in more than one way. The goal here is to show just the simplest which may mean displaying more than one command if they are about equally straightforward. In such cases the different commands are numbered with square brackets (e.g. “[1]”). Multiple commands generally mean multiple examples, which are similarly numbered.
- Most commands will work with PowerShell version 2 and above, though some require at least version 3. So if you are still running v2 and encounter an issue that is likely your culprit.
- The vast majority of commands are built-in, i.e. supplied by Microsoft. There are a few sprinkled about that require loading an additional module or script, but their usefulness makes them worth including in this compendium. These “add-ins” will be demarcated with angle brackets, e.g. <<pscx>> denotes the popular PowerShell Community Extensions (http://pscx.codeplex.com/).
- There are many links included for further reading; these are active hyperlinks that you may select if you are working online, but the URLs themselves are also explicitly provided (as in the previous bullet) in case you have a paper copy.
Note: Out of necessity, the version of the tables in the articles is somewhat compressed. If you find them hard to read, then there is a wide version of the article available here, and a PDF version is available from the link at the bottom of the article
Variables Here, There, and Everywhere
Because PowerShell is a shell language you can create complex and powerful operations on the command line. Because PowerShell is a programming language, you can also store that output into variables along the way. Thus, while item 1 demonstrates defining a variable with a simple value, you can use virtually any PowerShell expression for the indicated value. Part 2 will show further examples of variables containing collections and hash tables.
|
# |
Action |
Element |
Example |
Output |
|
1 |
Define variable |
[1] $name = value [2] value | Set-Variable -name name |
[1] $a = 25; $a [2] 42 | sv a; $a |
25 42 |
|
2 |
Define variable with auto-validation (see Validating Parameter Input at http://bit.ly/MtpW4K) |
[constraint]$name = value |
[1] [ValidateRange(1,10)][int]$x = 1; $x = 22 [2] [ValidateLength(1,25)][string]$s = “” |
–error– |
|
3 |
Variable uninterpreted within string |
‘… variable …’ (single quotes) |
$a = 25; ‘$a not interpolated’ |
$a not interpolated |
|
4 |
Scalar variable interpolated in string |
“… variable …” (double quotes) |
$a = 25; “$a interpolated” |
25 interpolated |
|
5 |
Array variable interpolated in string |
“… variable …” (double quotes) |
$arr = “aaa”,”bbb”,”x”; “arr is [$arr]” |
arr is [aaa bbb x] |
|
6 |
Array in string with non-default separator |
$OFS=’string’; “array-variable” |
$arr = “aaa”,”bbb”,”x”; $OFS=’/’; “arr is [$arr]” |
arr is [aaa/bbb/x] |
|
7 |
Complex syntactic element interpolated in string |
$(…) |
$myArray=@(1,2); “first element = $($myArray[0])” |
first element = 1 |
|
8 |
Format output a la printf (see Composite Formatting http://bit.ly/1gawf5H) |
formatString -f argumentList |
[1] $href=”http://foo.com”; $title = “title”; “<a href= ‘{0}’>{1}</a>” -f $href, $title [2] @{a=5;b=25}.GetEnumerator() |%{“{0} => {1}” -f $_.key, $_.value} [3] “{0,-10} = {1,5}” -f “myName”, 25 |
[1] <a href= ‘http://foo.com’>title</a> [2] a => 5`r`nb => 25 [3] myName = 25 |
|
9 |
Implicit function or loop variable |
$PSItem or $_ |
ls | % { $_.name } |
|
|
10 |
Private scope (.NET equiv: private) Local scope (.NET equiv: current) Script scope (.NET equiv: internal) Global scope (.NET equiv: public) |
$private:name $name or $local:name $script:name $global:name |
||
|
11 |
List all user variables and PowerShell variables |
Get-ChildItem variable: |
dir variable: |
|
|
12 |
List all environment variables |
Get-ChildItem env: |
ls env: |
|
|
13 |
List specific variables |
Get-ChildItem env:wildcardExpr |
ls env:HOME* |
HOMEPATH \Users\ms HOMEDRIVE C: |
|
14 |
Test if variable exists |
Test-Path variable:name |
If (!(Test-Path variable:ColorList)) { $ColorList = @() } |
Passing Parameters
Probably the most often-encountered issue with PowerShell is not understanding how to pass parameters to a PowerShell cmdlet or function. I suspect most folks start out confused about why it does not work, advance to being sure it is a bug in PowerShell, then finally achieve enlightenment and acceptance of the way it really works. The fundamental rule of passing multiple parameters is simply this: use spaces not commas. The entries below illustrate all the scenarios you would likely need.
|
# |
Action |
Command |
Example |
|
1 |
Pass multiple parameters inline |
cmdlet paramA paramB paramC (spaces-not commas!) |
# compare this result with inserting a comma between 5 and 3 function func($a,$b) { “{0}/{1}” -f $a.length, $b.length }; func 5 3 |
|
2 |
Pass multiple parameters from array (uses splatting operator; see http://stackoverflow.com/a/17198115/115690) |
$a = valueA, valueB, valueC; cmdlet @a |
# compare this result with using $a instead of @a function func($a,$b) { “{0}/{1}” -f $a.length, $b.length }; $a = 5, 3; func @a |
|
3 |
Pass an array of values as a single parameter inline |
cmdlet valueA, valueB, valueC |
dir prog.exe, prog.exe.config |
|
4 |
Pass an array of values as a single parameter in an array |
$a = valueA, valueB, valueC; cmdlet $a |
$a = “prog.exe”, “prog.exe.config”; dir $a |
|
5 |
Pass an array of values as a single parameter in a pipe |
valueA, valueB, valueC | cmdlet |
“prog.exe”, “prog.exe.config” | dir |
Properties
Properties really take center-stage in PowerShell, perhaps even more so than variables. With PowerShell, you are passing around objects but what you are actually using are their properties. If you invoke, for example, Get-Process, you get a table where each row contains the properties of a returned process. Get-Process by default outputs 8 properties (Handles, Name, etc.). There are actually dozens more, though, and you could show whichever ones you like simply by piping Get-Process into Select-Object. In terse form you might write ps | select -prop Name, StartTime. The entries in this section provide a good grounding in the nature of properties: how to show some or all of them, how to see if one exists, how to add or remove them, and so forth. Possibly the most exciting: if you have worked extensively in .NET you have likely wanted some way to dump complex objects for examination-a non-trivial task requiring either writing your own dumper or using a library. With PowerShell-just one command (entry 22).
|
# |
Action |
Command |
Example |
Output |
|
1 |
Test if property exists |
Get-Member -InputObject object -Name propertyName |
[1] “{0},{1}” -f [bool](gm -input (1..5) -name count), (1..5).count [2] [bool](gm -input (1..10) -name stuff) |
True,5 False |
|
2 |
Filter output displaying default properties |
any | Where-Object |
ps | ? { $_.VM -gt 100MB } |
|
|
3 |
Filter output displaying selected properties |
any | Where-Object | Select-Object |
ps | ? { $_.VM -gt 100MB } | select name, vm |
|
|
4 |
Display default properties in default format |
any |
[1] Get-Process uses Format-Table [2] Get-WmiObject win32_diskdrive uses Format-List |
|
|
5 |
Display default properties (table) |
any | Format-Table |
ps | ? { $_.Name -match “^m” } | ft |
|
|
6 |
Display default properties (list) |
any | Format-List |
ps | ? { $_.Name -match “^m” } | fl |
|
|
7 |
Display default properties (grid) |
any |Out-GridView |
Get-PsDrive | Out-GridView |
|
|
8 |
Display all properties (table) |
any | Format-Table -force * |
ps | ft -force * |
|
|
9 |
Display all properties (list) |
any | Format-List -force * |
gwmi win32_diskdrive | fl -force * |
|
|
10 |
Display all properties (grid) |
any | Select-Object *| Out-GridView |
Get-PsDrive | Select * | Out-GridView |
|
|
11 |
Display selected properties (table) |
any | Format-Table -Property wildcardExpr |
ps | ? { $_. Name -match “^m” } | ft st* |
|
|
12 |
Display selected properties (list) |
any | Format-List -Property wildcardExpr |
ps | ? { $_. Name -match “^m” } | fl st* |
|
|
13 |
Display selected properties (list or table) |
any | Select-Object -Property wildcardExpr |
ps | ? { $_. Name -match “^m” } | select s* (list) ps | ? { $_. Name -match “^m” } | select start* (table) |
|
|
14 |
Display calculated property |
any | Select-Object @{Name = name;Expression = scriptBlock} |
ls . | select Name, |
Name Kbytes —- —— file1.txt 1,088 file2.txt 269 . . . |
|
15 |
Add one property to an object |
[1] $obj | Add-Member -MemberType NoteProperty [2] $obj | Add-Member -NotePropertyName name |
$a = New-Object PSObject; $a | Add-Member “foo” “bar”; $a |
foo — bar |
|
16 |
Add multiple properties to a new object |
$obj = New-Object PSObject -Property hashTable |
$properties = @{name=”abc”; size=12; entries=29.5 }; $a = New-Object PSObject -Property $properties; $a | ft -auto |
entries name size ——- —- —- 29.5 abc 12 |
|
17 |
Add multiple properties to an existing object |
$obj | Add-Member -NotePropertyMembers hashTable |
$a | Add-Member -NotePropertyMembers @{ “x”=5;”y”=1}; $a |
entries name size x y ——- —- —- – – 29.5 abc 12 5 1 |
|
18 |
Remove a property from one object |
$obj.PSObject.Properties.Remove(propertyName) |
$a.PSObject.Properties.Remove(“name”) |
entries size ——- —- 29.5 12 |
|
19 |
Remove property from a collection of objects (Remove a Member from a PowerShell Object?) |
any | Select-Object -Property * |
ls | select -property * -exclude Mode |
|
|
20 |
List property names of an object type |
any | Get-Member -MemberType Property |
($PWD | gm -Member Property).Name |
Drive Path Provider ProviderPath |
|
21 |
List property names with their associated values (really shallow) |
[1] any | Format-List [2] any | Select-Object -Property * |
[1] $PWD | fl [2] $PWD | select * |
Drive : C Provider : Core\FileSystem ProviderPath : C:\usr Path : C:\usr |
|
22 |
List property names with their associated values (adjustable shallow to deep) |
any | ConvertTo-Json -Depth depth |
$PWD | ConvertTo-Json -Depth 1 |
(This last snippet, no. 22, is just one-level deeper than the “really shallow” approach in the previous entry (21). But wherever you see type names, there is still room for further expansion-just increase the depth value. Note that the list will get very big very fast-even a depth of 3 is quite voluminous!)
Objects, Types and Casts
This section provides some insights into .NET objects in PowerShell: seeing what type something is or testing if an object is a certain type; accessing .NET enumeration values; casting objects to different types; cloning objects.
|
# |
Action |
Command |
Example |
Output |
|
1 |
Get size of collection |
[1] @(any).Count [2] any | Measure-Object |
[1] @(Get-Process).Count [2] (Get-Process | Measure-Object).Count |
|
|
2 |
Get type of non-collection or object array for collection (i.e. does not report base type of array) |
object.GetType().FullName
|
[1] “abc”.GetType().FullName [2] (1,2,3).GetType().FullName [3] (“a”, “b”, “c”).GetType().FullName |
System.String System.Object[] System.Object[] |
|
3 |
Get type of any object or base type of array |
object | Get-Member | Select -First 1 |%{$_.TypeName} |
[1] 1,2,3 | gm | select -First 1| % { $_.TypeName } [2] 1 | gm | select -First 1| % { $_.TypeName } |
System.Int32 System.Int32 |
|
4 |
Get base type of non-empty array |
array[0].GetType().FullName |
$myArray[0].GetType().FullName |
|
|
5 |
Get object hierarchy |
object.PsTypeNames |
(gci | select -First 1). PsTypeNames |
System.IO.DirectoryInfo System.IO.FileSystemInfo System.MarshalByRefObject System.Object |
|
6 |
Test type |
if (object -is type) . . . |
“hello” -is [string] |
True |
|
7 |
Access .NET enumeration type |
[typeName]::enumValue |
“/A/B/C//D/E//F/G” .Split(“/”, [System.StringSplitOptions]::ÂRemoveEmptyEntries) |
|
|
8 |
Combine bitwise .NET enum type values |
[typeName]::enumValue -bor [typeName]::enumValue |
[System.ÂText.ÂRegularExpressions.ÂRegexOptions]::ÂSingleline -bor [System.ÂText.ÂRegularExpressions.ÂRegexOptions]::ÂExplicitCapture |
|
|
9 |
Cast string to integer (about_Type_Operators: http://bit.ly/1a1aMyp) |
string -as [int] |
[1] “foo” -as [int] [2] “35.2” -as [int] [3] “0.0” -as [int] |
35 0 |
|
10 |
Test cast string to integer |
[bool]($var -as [int] -is [int]) |
[1] “foo” -as [int] -is [int] [2] “35.2” -as [int] -is [int] |
False True |
|
11 |
Convert ASCII code to character |
[char]integer |
[1] [char]48 [2] [char]0x42 |
0 B |
|
12 |
Convert character to ASCII code |
[byte][char]character |
[byte][char] “A” |
65 |
|
13 |
Convert integer to hexadecimal |
“0x{0:x}” -f integer |
“0x{0:x}” -f 64 |
0x40 |
|
14 |
Convert hexadecimal to integer |
hex-value |
0x40 |
64 |
|
15 |
Test if command exists |
Get-Command command -errorAction SilentlyContinue |
[1] [bool](gcm Get-ChildItem -ea SilentlyContinue) [2] [bool](gcm Get-MyStuff -ea SilentlyContinue) |
True False |
|
16 |
Clone object |
$newObj = $oldObj | Select-Object * |
||
|
17 |
Clone object except for specific property |
$newObj = $oldObj | Select-Object * -except property |
||
|
18 |
Identify type of each returned object (Example: Get-ChildItem may return DirectoryInfo or FileInfo objects) |
any | Select-Object id-field, type-expression |
[1] Get-ChildItem | select name, [2] Get-Alias | select name, @{n=’type’;e={$_.ReferencedCommand.GetType().Name}} |
Encapsulation Does a Program Good
Because PowerShell is not just a shell but also a rich scripting language, it supports encapsulation at multiple levels. Scripts provide simple physical separation for your code while modules provide both physical and logical separation. That is, modules let you separate context or scope, so they are well worth the additional effort to set up. In a related vein, it is helpful to be cognizant of command precedence: alias, function, cmdlet, script, application. So, if there is a function and cmdlet of the same name, for example, then the function will be executed when you invoke that name because of precedence rules.
|
# |
Action |
Command |
Example |
|
1 |
Check permissions for running scripts |
Get-ExecutionPolicy |
same |
|
2 |
Set permissions for running scripts |
Set-ExecutionPolicy policy |
Set-ExecutionPolicy RemoteSigned |
|
3 |
Run a script in current context (dot-sourcing) |
. path\script.ps1 |
echo ‘$foo = “hello now” ‘ > tmp\trial.ps1 $foo # empty . tmp\trial # dot-source the file $foo # now contains ‘hello now’ |
|
4 |
Run a script in child context |
& path\script.ps1 |
echo ‘$foo = “hello now” ‘ > tmp\trial.ps1 $foo # empty tmp\trial # execute script $foo # still empty! |
|
5 |
Get directory of currently running script |
$PSScriptRoot (use Split-Path $script:MyInvocation.MyCommand.Path for v2) |
$scriptDir = Split-Path $script:MyInvocation.MyCommand.Path $scriptDir = $PSScriptRoot |
|
6 |
Load module x.psm1 from standard location |
Import-Module module |
Import-Module foo |
|
7 |
Load module x.psm1 from arbitrary location |
Import-Module path\module |
Import-Module \usr\ps\mymodules\foo |
|
8 |
List cmdlets added by a loaded module |
Get-Command -Module module |
gcm -Module sqlps |
|
9 |
List loaded modules |
Get-Module |
same |
|
10 |
List modules available to load |
Get-Module -ListAvailable |
same |
|
11 |
See what other details to glean about modules |
Get-Module | Get-Member |
gmo | gm -type property |
|
12 |
List modules with custom-specified properties |
gmo | Format-Table -p property, property, … |
gmo | ft -p name, moduletype, author, version -auto |
|
13 |
List contents of a public function |
[1] Get-Content function:name [2] (Get-ChildItem function:name).Definition [3] (Get-Command name).ScriptBlock |
[1] gc function:Get-Verb [2] (gci function:Get-Verb).definition [3] (gcm Get-Verb).ScriptBlock |
|
14 |
List contents of a private function |
& ( Get-Module module ) { Get-Content function:name } |
# create a Test module with a function foobar, import it, then run: & (gmo Test) { Get-Content function:foobar } |
|
15 |
Determine source of duplicate names (e.g. cmdlet and function imported with the same name) |
Get-Command name | select CommandType, Name, ModuleName |
# The PS Community extensions has another version of Get-Help: Import-Module pscx; gcm get-help | select CommandType, name, modulename |
|
16 |
Trace parameter assignment in cmdlet |
Trace-Command -psHost -Name ParameterBinding { expression } |
Trace-Command -psHost -Name ParameterBinding { “abc”, “Abc” | select -unique } |
|
17 |
Trace parameter assignment in own functions |
Write-Host $PSBoundParameters |
function foo($a, $b) { Write-Host $PSBoundParameters }; foo “one” “two” |
|
18 |
Support wildcards passed as parameters (see How to pass a list of files as parameters to a powershell script) |
Param ( [String[]]$files ) |
The Meta-Verse: Profile, History, Version, Prompt
Here you can see how to check what version of PowerShell you are running (even switch to an earlier version if needed); select and run previously used commands by number or by substring; examine any of your numerous profiles (scripts run on PowerShell startup); and change your command prompt.
|
# |
Action |
Command |
Example |
|
1 |
Display PowerShell version |
$PsVersionTable.PSVersion (more reliable than $Host.Version – see How to determine what version of PowerShell is installed?) |
$PsVersionTable.PSVersion |
|
2 |
Display version and other info of one exe or dll |
(Get-Command path).FileVersionInfo (Get-Item path).VersionInfo | Format-List |
|
|
3 |
Display version and other info of multiple executables |
paths | Get-Command $_.FullName | Select -expand FileVersionInfo |
dir *.dll,*.exe | %{gcm $_.FullName} | select -expand File* |
|
4 |
Run an earlier version of PowerShell |
powershell -Version 2 |
same |
|
5 |
Get complete command history |
Get-History |
same |
|
6 |
Set maximum remembered commands |
$MaximumHistoryCount = integer |
$MaximumHistoryCount = 1000 |
|
7 |
Get last n commands from history |
Get-History -count n |
ghy -Count 25 |
|
8 |
Get last n commands from history containing substring |
Get-History | Select-String string | Select -last n |
h | sls child | Select -last 25 |
|
9 |
Run command from history by command number |
Invoke-History integer |
r 23 |
|
10 |
Run command from history by command substring |
#commandSubstring |
#child (assuming you recently ran e.g. Get-ChildItem); press <tab> to cycle through list of other “child” choices. |
|
11 |
View path to profile for [current user, current host] |
$PROFILE |
same |
|
12 |
View path to all profiles (see http://bit.ly/JfgXwO) |
$PROFILE | Format-List * -Force |
same |
|
13 |
Test whether profile exists for [current user, current host] |
Test-Path $PROFILE |
same |
|
14 |
Test whether particular profile exists |
Test-Path $PROFILE.profile |
Test-Path $PROFILE.CurrentUserCurrentHost |
|
15 |
Change your prompt (see here) |
Define prompt function in your profile |
function prompt { . . . } |
Running Other Programs
As a shell language supplanting DOS, you will likely want to execute other programs, just like Windows batch files. It is fairly straightforward but the entries here show you a few nuances that you should be aware of. You can also see how to review execution status, see how long something takes to execute, and even limit how much time something may execute.
|
# |
Action |
Command |
Example |
|
1 |
Execute a program in a separate process |
Start-Process program (NB: If using ISE you must use this to execute a program if the program reads from the console – see Why does PowerShell ISE hang on this C# program?) |
start tmp\demo.exe |
|
2 |
Open Windows Explorer at current directory |
[1] Start-Process . [2] explorer . |
same |
|
3 |
Execute a program in the same process |
program |
[1] C:\usr\progs\demo.exe [2].\demo.exe |
|
4 |
Execute a program with spaces in the name |
& “program” |
[1] & “C:\Program Files\demo.exe” [2] & “tmp\demo with spaces.exe” [3] & “.\demo in current dir.exe” |
|
5 |
Time a command |
Measure-Command scriptBlock |
Measure-Command { Get-Content stuff.txt } |
|
6 |
Time-limit a command |
$j = Start-Job -ScriptBlock { … } |
|
|
7 |
Execution status of last operation-use only for PowerShell commands (see PowerShell $LastExitCode=0 but $?=False . Redirecting stderr to stdout gives NativeCommandError) |
$? |
|
|
8 |
Execution status of last external command |
$LastExitCode |
|
|
9 |
Discard output (i.e. run commands for side effects) (see http://bit.ly/1cjmWSk) |
[1] any > $null [2] $null = any [3] any | Out-Null [4] [void] (any) |
Parsing and Grouping
While this heading might sound abstruse or obscure and you may be tempted to skip it-don’t! Understanding the fundamentals of grouping and command vs. expression parsing in PowerShell can make working in PowerShell much more fruitful. The entries here present a condensed reference-take a look at Keith Hill’s Understanding PowerShell Parsing Modes for more details.
|
# |
Action |
Element |
Example |
Output |
|
1 |
Grouping expression (single expression or pipeline) |
( command ) |
(dir C:\).length (dir C:\).name (ps | select -First 1).GetType().Name (ps | select -First 5).GetType().Name (“foo”; “bar”; “baz”).GetType().Name (“abc”).length (“foo”, “bar”).length |
scalar: a single number array: list of file names Process Object[] –error- 3 2 |
|
2 |
Subexpression Multiple statements allowed; single result returns scalar; multiple results return array. |
$( command-sequence ) |
$(ls c:\; ls c:\windows).length $(ps | select -First 1).GetType().Name $(ps | select -First 5).GetType().Name $(“foo”; “bar”; “baz”).GetType().Name $(“abc”).length $(“foo”, “bar”).length |
scalar: a single number Process Object[] Object[] 3 2 |
|
3 |
Array subexpression Multiple statements allowed; guarantees array result. |
@( command-sequence ) |
@(ls c:\; ls c:\windows).length @(ps | select -First 1).GetType().Name @(ps | select -First 5).GetType().Name @(“foo”; “bar”; “baz”).GetType().Name @(“abc”).length @(“foo”, “bar”).length |
scalar: a single number Object[] Object[] Object[] 1 2 |
|
4 |
Command parsing |
Begin with alpha, _, &, ., or \ |
dir file1.txt |
|
|
5 |
Expression parsing |
Begin with any character other than above |
“dir file1.txt” |
|
|
6 |
Parsing determination: start of command and at start of any subexpression |
Write-Host Get-ChildItem vs. Write-Host (Get-ChildItem) |
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|
7 |
Run custom cmdlet from batch |
powershell -command “import-module M1; cmdlet1” |
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|
8 |
Invoke dynamic code |
Invoke-Expression string |
iex “write-host hello” |
hello |
Conclusion
That’s it for part 2; keep an eye out for more in the near future! While I have been over the recipes presented numerous times to weed out errors and inaccuracies, I think I may have missed one. If you locate it, please share your findings in the comments below!
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