about_operators | Easy Powershell 2.0 Reference

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)
     to find patterns using regular expressions; the replace operator
     (-replace), which uses regular expressions to change input values; and
     the like operators (-like, -notlike), which find patterns using wildcard
     characters (*).

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.

     & Call operator
        Description: Runs a command, script, or script block. Because the call
        operator does not parse, it cannot interpret command parameters. The
        call operator, also known as the “invocation operator, indicates that
        the value it precedes is a command. This enables you to run commands
        stored in Variables and represented by strings. Examples:

            & “new cmdlet”
            $c = “Get-ExecutionPolicy”
            & $c

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

$myString.length
$myString.substring(1,3)

     . dot sourcing operator
        Description: Runs a script so that the items in the script are part
        of the calling scope. For more information, see about_Scopes/”>about_Scope. Example:

. c:\scripts.sample.ps1

Note: The dot (.) symbol is also used as the parent directory symbol,
as in this example:

.\sample.ps1

This command runs the sample.ps1 script, but not as part of the
calling scope.

     :: Static member operator
        Description: 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. Example:

[datetime]::now

     .. Range operator
        Description: Represents the sequential integers in an integer array,
        given an upper and lower boundary. Examples:

            1..10
            10..1
            foreach ($a in 1..$max) {Write-Host $a}

     -f Format operator
        Description: 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.
        Examples:

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

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

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

     @( ) Array subexpression operator
        Description: Returns the result of one or more statements as an array.
        If there is only one item, the array has only one member. Example:

@(Get-WmiObject win32_logicalDisk)

     , operator
        Description: 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. Examples:

$myArray = 1,2,3
$SingleArray = ,1