TOPIC
	about_Operators

SHORT DESCRIPTION
	Describes the operators that are supported by Windows PowerShell. 

LONG DESCRIPTION
	An operator is a language element that you can use in a command or
	expression. Windows 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.


	You can also use arithmetic operators with strings, arrays, and hash 
	tables. The addition operator concatenates elements. The multiplication
	operator returns the specified number of copies of each element.


	For more information, see about_Arithmetic_Operators. 


  Assignment Operators
	Use assignment operators (=, +=, -=, *=, /=, %=) to assign one or more
	values to variables, to change the values in a variable, and to append
	values to variables. You can also cast the variable as any Microsoft .NET
	Framework data type, such as string or DateTime, or Process 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 include the match operators (-match, -notmatch), 
	which find patterns by using regular expressions; the replace operator 
	(-replace), which uses regular expressions to change input values; the
	like operators (-like, -notlike), which find patterns using wildcard 
	characters (*); and the containment operators (-contains, -notcontains),
	which determine whether a test value appears in a reference set.


	They also include the bitwise operators (-bAND, -bOR, -bXOR, -bNOT) to 
	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
	Use special operators to perform tasks that cannot be performed by the 
	other types of operators. For example, special operators allow you to 
	perform operations such as running commands and changing a value's data 
	type.



	@( ) 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-WMIObject 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. Because the call operator does not
		 parse the command, it cannot interpret command parameters. 

			 C:\PS> $c = "get-executionpolicy"
			 C:\PS> $c
			 get-executionpolicy
 
			 C:\PS> & $c
			 AllSigned



	[ ] Cast operator
		 Converts or limits objects to the specified type. If the objects
		 cannot be converted, Windows PowerShell generates an error.

			 [datetime]$birthday = "1/20/88"
			 [int64]$a = 34  



	, 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



	-f Format operator
		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.
	

			 C:\PS> "{0} {1,-10} {2:N}" -f 1,"hello",[math]::pi
			 1 hello	3.14

		For more information, see the String.Format method 
		(http://go.microsoft.com/fwlink/?LinkID=166450) and 
		Composite Formatting (http://go.microsoft.com/fwlink/?LinkID=166451).



	[ ] 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.

			 C:\PS> $a = 1, 2, 3
			 C:\PS> $a[0]
			 1
			 C:\PS> $a[-1]
			 3


			 C:\PS> (get-hotfix | sort installedOn)[-1]

		 
			 C:\PS> $h = @{key="value"; name="Windows PowerShell"; version="2.0"}
			 C:\PS> $h["name"]
			 Windows PowerShell


			 C:\PS> $x = [xml]"<doc><intro>Once upon a time...</intro></doc>"
			 C:\PS> $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 {$_.vendor -ne "Microsoft"}						



	. Property dereference operator
		 Accesses the properties and methods of an object. 
		 

			 $myProcess.peakWorkingSet
			 (get-process powershell).kill()



	.. 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}



	:: Static member operator
		Calls the static properties operator 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
   



	$( ) Subexpression operator
		 Returns the result of one or more statements. For a 
		 single result, returns a scalar. For multiple results, returns an 
		 array.


			 $($x * 23)
			 $(Get-WMIObject win32_Directory)

					 


	 
SEE ALSO
	about_Arithmetic_Operators
	about_Assignment_Operators
	about_Comparison_Operators
	about_Logical_Operators
	about_Type_Operators
	about_Split
	about_Join
	about_Redirection