| Server IP : 134.29.175.74 / Your IP : 216.73.216.160 Web Server : nginx/1.10.2 System : Windows NT CST-WEBSERVER 10.0 build 19045 (Windows 10) i586 User : Administrator ( 0) PHP Version : 7.1.0 Disable Function : NONE MySQL : OFF | cURL : ON | WGET : OFF | Perl : OFF | Python : OFF | Sudo : OFF | Pkexec : OFF Directory : C:/Windows/SysWOW64/WindowsPowerShell/v1.0/en-US/ |
Upload File : |
ABOUT OPERATORS
Short description
Describes the operators that are supported by PowerShell.
Long description
An operator is a language element that you can use in a command or
expression. PowerShell supports several types of operators to help you
manipulate values.
Arithmetic Operators
Use arithmetic operators (+, -, *, /, %) to calculate values in a command
or expression. With these operators, you can add, subtract, multiply, or
divide values, and calculate the remainder (modulus) of a division
operation.
The addition operator concatenates elements. The multiplication operator
returns the specified number of copies of each element. You can use
arithmetic operators on any .NET type that implements them, such as: Int,
String, DateTime, Hashtable, and Arrays.
For more information, see about_Arithmetic_Operators.
Assignment Operators
Use assignment operators (=, +=, -=, *=, /=, %=) to assign, change, or
append values to variables. You can combine arithmetic operators with
assignment to assign the result of the arithmetic operation to a variable.
For more information, see about_Assignment_Operators.
Comparison Operators
Use comparison operators (-eq, -ne, -gt, -lt, -le, -ge) to compare values
and test conditions. For example, you can compare two string values to
determine whether they are equal.
The comparison operators also include operators that find or replace
patterns in text. The (-match, -notmatch, -replace) operators use regular
expressions, and (-like, -notlike) use wildcards *.
Containment comparison operators determine whether a test value appears in
a reference set (-in, -notin, -contains, -notcontains).
Type comparison operators (-is, -isnot) determine whether an object is of a
given type.
Bitwise comparison operators (-bAND, -bOR, -bXOR, -bNOT) manipulate the bit
patterns in values.
For more information, see about_Comparison_Operators.
Logical Operators
Use logical operators (-and, -or, -xor, -not, !) to connect conditional
statements into a single complex conditional. For example, you can use a
logical -and operator to create an object filter with two different
conditions.
For more information, see about_Logical_Operators.
Redirection Operators
Use redirection operators (>, >>, 2>, 2>>, and 2>&1) to send the output of
a command or expression to a text file. The redirection operators work like
the Out-File cmdlet (without parameters) but they also let you redirect
error output to specified files. You can also use the Tee-Object cmdlet to
redirect output.
For more information, see about_Redirection
Split and Join Operators
The -split and -join operators divide and combine substrings. The -split
operator splits a string into substrings. The -join operator concatenates
multiple strings into a single string.
For more information, see about_Split and about_Join.
Type Operators
Use the type operators (-is, -isnot, -as) to find or change the .NET
Framework type of an object.
For more information, see about_Type_Operators.
Unary Operators
Use unary operators to increment or decrement variables or object
properties and to set integers to positive or negative numbers. For
example, to increment the variable $a from 9 to 10, you type $a++.
Special Operators
Special operators have specific use-cases that do not fit into any other
operator group. For example, special operators allow you to run commands,
change a value's data type, or retrieve elements from an array.
Grouping operator ( )
As in other languages, (...) serves to override operator precedence in
expressions. For example: (1 + 2) / 3
However, in PowerShell, there are additional behaviors.
- (...) allows you to let output from a _command_ participate in an
expression. For example:
PS> (Get-Item *.txt).Count -gt 10
True
- When used as the first segment of a pipeline, wrapping a command or
expression in parentheses invariably causes _enumeration_ of the
expression result. If the parentheses wrap a _command_, it is run to
completion with all output _collected in memory_ before the results are
sent through the pipeline.
[!NOTE] Wrapping a command in parentheses causes the automatic variable
$? to be set to $true, even when the enclosed command itself set $? to
$false. For example, (Get-Item /Nosuch); $? unexpectedly yields TRUE. For
more information about $?, see about_Automatic_Variables.
Subexpression operator $( )
Returns the result of one or more statements. For a single result, returns
a scalar. For multiple results, returns an array. Use this when you want to
use an expression within another expression. For example, to embed the
results of command in a string expression.
PS> "Today is $(Get-Date)"
Today is 12/02/2019 13:15:20
PS> "Folder list: $((dir c:\ -dir).Name -join ', ')"
Folder list: Program Files, Program Files (x86), Users, Windows
Array subexpression operator @( )
Returns the result of one or more statements as an array. If there is only
one item, the array has only one member.
@(Get-CimInstance win32_logicalDisk)
Call operator &
Runs a command, script, or script block. The call operator, also known as
the "invocation operator", lets you run commands that are stored in
variables and represented by strings or script blocks. The call operator
executes in a child scope. For more about scopes, see about_Scopes.
This example stores a command in a string and executes it using the call
operator.
PS> $c = "get-executionpolicy"
PS> $c
get-executionpolicy
PS> & $c
AllSigned
The call operator does not parse strings. This means that you cannot use
command parameters within a string when you use the call operator.
PS> $c = "Get-Service -Name Spooler"
PS> $c
Get-Service -Name Spooler
PS> & $c
& : The term 'Get-Service -Name Spooler' is not recognized as the name of a
cmdlet, function, script file, or operable program. Check the spelling of
the name, or if a path was included, verify that the path is correct and
try again.
At line:1 char:2
+ & $c
+ ~~
+ CategoryInfo : ObjectNotFound: (Get-Service -Name Spooler:String) [], CommandNotFoundException
+ FullyQualifiedErrorId : CommandNotFoundException
The Invoke-Expression cmdlet can execute code that causes parsing errors
when using the call operator.
PS> & "1+1"
& : The term '1+1' is not recognized as the name of a cmdlet, function, script
file, or operable program. Check the spelling of the name, or if a path was
included, verify that the path is correct and try again.
At line:1 char:2
+ & "1+1"
+ ~~~~~
+ CategoryInfo : ObjectNotFound: (1+1:String) [], CommandNotFoundException
+ FullyQualifiedErrorId : CommandNotFoundException
PS> Invoke-Expression "1+1"
2
You can use the call operator to execute scripts using their filenames. The
example below shows a script filename that contains spaces. When you try to
execute the script, PowerShell instead displays the contents of the quoted
string containing the filename. The call operator allows you to execute the
contents of the string containing the filename.
PS C:\Scripts> Get-ChildItem
Directory: C:\Scripts
Mode LastWriteTime Length Name
---- ------------- ------ ----
-a---- 8/28/2018 1:36 PM 58 script name with spaces.ps1
PS C:\Scripts> ".\script name with spaces.ps1"
.\script name with spaces.ps1
PS C:\Scripts> & ".\script name with spaces.ps1"
Hello World!
For more about script blocks, see about_Script_Blocks.
Cast operator [ ]
Converts or limits objects to the specified type. If the objects cannot be
converted, PowerShell generates an error.
[DateTime]"2/20/88" - [DateTime]"1/20/88"
[Int] (7/2)
[String] 1 + 0
[Int] '1' + 0
A cast can also be performed when a variable is assigned to using cast
notation.
Comma operator ,
As a binary operator, the comma creates an array. As a unary operator, the
comma creates an array with one member. Place the comma before the member.
$myArray = 1,2,3
$SingleArray = ,1
Dot sourcing operator .
Runs a script in the current scope so that any functions, aliases, and
variables that the script creates are added to the current scope.
. c:\scripts\sample.ps1
[!NOTE] The dot sourcing operator is followed by a space. Use the space
to distinguish the dot from the dot (.) symbol that represents the
current directory.
In the following example, the Sample.ps1 script in the current directory is
run in the current scope.
. .\sample.ps1
Format operator -f
Formats strings by using the format method of string objects. Enter the
format string on the left side of the operator and the objects to be
formatted on the right side of the operator.
"{0} {1,-10} {2:N}" -f 1,"hello",[math]::pi
1 hello 3.14
For more information, see the String.Format method and Composite
Formatting.
Index operator [ ]
Selects objects from indexed collections, such as arrays and hash tables.
Array indexes are zero-based, so the first object is indexed as [0]. For
arrays (only), you can also use negative indexes to get the last values.
Hash tables are indexed by key value.
PS> $a = 1, 2, 3
PS> $a[0]
1
PS> $a[-1]
3
(Get-HotFix | Sort-Object installedOn)[-1]
$h = @{key="value"; name="PowerShell"; version="2.0"}
$h["name"]
PowerShell
$x = [xml]"<doc><intro>Once upon a time...</intro></doc>"
$x["doc"]
intro
-----
Once upon a time...
Pipeline operator |
Sends ("pipes") the output of the command that precedes it to the command
that follows it. When the output includes more than one object (a
"collection"), the pipeline operator sends the objects one at a time.
Get-Process | Get-Member
Get-PSSnapin | Where-Object {$_.vendor -ne "Microsoft"}
Range operator ..
Represents the sequential integers in an integer array, given an upper, and
lower boundary.
1..10
10..1
foreach ($a in 1..$max) {Write-Host $a}
Member access operator .
Accesses the properties and methods of an object.
$myProcess.peakWorkingSet
(Get-Process PowerShell).kill()
Static member operator ::
Calls the static properties and methods of a .NET Framework class. To find
the static properties and methods of an object, use the Static parameter of
the Get-Member cmdlet.
[datetime]::Now
See also
about_Arithmetic_Operators
about_Assignment_Operators
about_Comparison_Operators
about_Logical_Operators
about_Operator_Precedence
about_Type_Operators
about_Split
about_Join
about_Redirection