As has been noted, methods of .NET types such as System.String.Split() are not part of PowerShell, but of the .NET framework that PowerShell is built on, so you'll have to consult the official documentation at https://docs.microsoft.com.
That said, given the close integration between PowerShell and .NET, it would be nice to be able to easily consult this documentation from within PowerShell - see this GitHub suggestion.
However, operators such as -split are PowerShell language features, and both discovering their documentation altogether and getting focused, operator-specific information is currently cumbersome.
Documentation for language features such as operators is contained in about_* help topics, which can be targeted with Get-Help -Category HelpFile, and you can combine that with passing the (quoted) name of the operator in order to search the contents of these topics:
- For example,
Get-Help -Category HelpFile -Name '-replace' at least narrows the search down, but still includes all help topics that mention -replace; the result will comprise the about_Operators help topic, which is the overview page that links to more specific pages focused on specific categories of operators, such as arithmetic operators, comparison operators, ..., but also describes some general-purpose operators directly.
There is currently no direct way to get focused information for a given operator, but there should be: see this GitHub suggestion.
Below are two helper functions that try to overcome the current limitations (as of v7.0), Show-OperatorHelp and Show-TypeHelp.
Note:
Both functions (of necessity) don't show the documentation in the console (terminal), but open the online documentation in your default web browser.
In Show-TypeHelp, support is limited to those (public) types that ship with .NET and therefore have documentation pages at https://docs.microsoft.com.
Show-OperatorHelp opens the specific section describing just the operator of interest whenever possible; some operators, such as the arithmetic operators +, -, don't have individual sections, but the overall topic is usually short enough in these cases to make it easy to find the parts of interest.
They come with comment-based help, so you can use -? and Get-Help to learn more about them.
You can place them in your $PROFILE file, for instance, or - given their length - you may want to create external scripts (*.ps1) based on them that you place in a directory listed in $env:Path. To that end, simply strip the function <name> { line and the final } and save them to a *.ps1 file.
Example uses:
Show-OperatorHelp:
# Opens the home (overview) page for all PowerShell operators
Show-OperatorHelp
# Lists all operators in the console,
# along with their friendly names and categories.
Show-OperatorHelp -List
# Opens the help topic (section) for the -replace operator.
# Equivalent of
Show-OperatorHelp -Name '-replace'
# because you omit the initial '-'; if you do specify it, quote the entire argument.
Show-OperatorHelp replace
# Opens the help topic (section) for @(...), the array-subexpression operator.
# Note the need for quoting.
Show-OperatorHelp '@()'
Show-TypeHelp:
# Opens the documentation for the System.String.Split() method.
# You can specify a type name ('string' in this example) as follows:
# * Use a full type name, with the initial 'System.' component optionally omitted (e.g. 'Text.Encoding' for 'System.Text.Encoding'
# * Use a type accelerator such as 'xml' for 'System.Xml.XmlDocument'
# Tab-completion: You can type (part of) a the name of a type
# (last component of the full name) and cycle through loaded types by that name.
# E.g., typing `arrayli` tab-completes to 'System.Collections.ArrayList'.
# Alternatively, *pipe* an instance of a string to the function (see next example).
Show-TypeHelp string split # Short for: Show-TypeHelp -Type string -Member split
# Opens the documentation for the [Microsoft.PowerShell.Commands.MatchInfo]
# type, instances of which Select-String outputs.
'foo' | Select-String o | Show-TypeHelp
I suggest getting the source code from the following MIT-licensed Gists instead, as only they will be maintained; assuming you have looked at the code (which I can personally assure you is safe, but you should always check), you can install them directly:
irm https://gist.github.com/mklement0/146f3202a810a74cb54a2d353ee4003f/raw/Show-OperatorHelp.ps1 | iex
irm https://gist.github.com/mklement0/50a1b101cd53978cd147b4b138fe6ef4/raw/Show-TypeHelp.ps1 | iex
Note: Ignore the broken syntax highlighting below.
Show-OperatorHelp source code:
function Show-OperatorHelp {
<#
.SYNOPSIS
Shows documentation for PowerShell's operators.
.DESCRIPTION
Navigates to operator-specific or -related online help topics in your default
web browser.
Invoke argument-less to see the operators overview help topic.
-Precedence shows the topic about operator precedence.
-QuotingRules shows the topic about string literals and quoting.
-Name <name> targets a specific operator.
.PARAMETER Name
The name of an operator.
Note that most names must be passed *in quotes* for syntactic reasons;
e.g., '-match' instead of -match
However, you may omit the initial '-', in which case you needn't quote.
Use -List to see all names.
.PARAMETER Precedence
Opens the help topic that describes operator precedence.
.PARAMETER List
Parameter description
.PARAMETER QuotingRules
Opens the help topic that describes the quoting rules and syntax for
string literals.
.PARAMETER CopyUrl
Instead of opening the topic page in a browser, copies the page's URL to
the clipboard.
.PARAMETER Version
Specify a specific PowerShell version number (e.g., 7 or 5.1) for which to
display the requested help topic.
By default, the executing engine's version number is used.
.EXAMPLE
Show-OperatorHelp
Opens the home (overview) page for all PowerShell operators.
.EXAMPLE
Show-OperatorHelp replace
Opens the help topic (section) for the -replace operator.
Equivalent of: Show-OperatorHelp -Name '-replace'
.EXAMPLE
Show-OperatorHelp -List
Lists all operators, along with their friendly names and categories.
.EXAMPLE
Show-OperatorHelp -Precedence
Shows the help topic about operator precedence.
#>
[CmdletBinding(DefaultParameterSetName = 'HomePage', SupportsShouldProcess, PositionalBinding = $false)]
param (
[Parameter(ParameterSetName = 'Name', Mandatory, Position = 0)]
[string] $Name
,
[Parameter(ParameterSetName = 'Precedence')]
[switch] $Precedence
,
[Parameter(ParameterSetName = 'List')]
[Alias('ListAvailable')]
[switch] $List
,
[Parameter(ParameterSetName = 'QuotingRules')]
[Alias('StringLiterals')]
[switch] $QuotingRules
,
[Parameter(ParameterSetName = 'Name')]
[Parameter(ParameterSetName = 'Precedence')]
[Parameter(ParameterSetName = 'QuotingRules')]
[Parameter(ParameterSetName = 'HomePage')]
[Alias('cp')]
[switch] $CopyUrl
,
[Parameter(ParameterSetName = 'Name')]
[Parameter(ParameterSetName = 'Precedence')]
[Parameter(ParameterSetName = 'QuotingRules')]
[Parameter(ParameterSetName = 'HomePage')]
[string] $Version # PowerShell version
)
# Default to the executing PowerShell engine's version.
# Note: If no "?view=powershell-<ver>" query string is present,
# the currently highest stable version overall is targeted.
if ($Version) {
$verObj = $Version -as [version]
if (-not $verObj) { $verObj = "$Version.0" -as [version] }
if (-not $verObj) { Throw "Unrecognized PowerShell version number: $Version" }
}
else {
$verObj = $PSVersionTable.PSVersion
}
$Version = ('{0}.{1}' -f $verObj.Major, $verObj.Minor) -replace '.0$'
$opTable = @{
# about_Arithmetic_Operators
'-' = [pscustomobject] @{ Name = '-'; FriendlyName = 'subtraction / sign inversion'; Topic = 'about_Arithmetic_Operators'; Category = 'Arithmetic' }
'*' = [pscustomobject] @{ Name = '*'; FriendlyName = 'multiplication / string replication'; Topic = 'about_Arithmetic_Operators'; Category = 'Arithmetic' }
'/' = [pscustomobject] @{ Name = '/'; FriendlyName = 'division'; Topic = 'about_Arithmetic_Operators'; Category = 'Arithmetic' }
'%' = [pscustomobject] @{ Name = '%'; FriendlyName = 'modulus'; Topic = 'about_Arithmetic_Operators'; Category = 'Arithmetic' }
'+' = [pscustomobject] @{ Name = '+'; FriendlyName = 'addition / string conatenation'; Topic = 'about_Arithmetic_Operators'; Category = 'Arithmetic' }
'-band' = [pscustomobject] @{ Name = '-band'; FriendlyName = 'bitwise AND'; Topic = 'about_Arithmetic_Operators'; Category = 'Bitwise' }
'-bor' = [pscustomobject] @{ Name = '-bor'; FriendlyName = 'bitwise OR'; Topic = 'about_Arithmetic_Operators'; Category = 'Bitwise' }
'-bxor' = [pscustomobject] @{ Name = '-bxor'; FriendlyName = 'bitwise XOR'; Topic = 'about_Arithmetic_Operators'; Category = 'Bitwise' }
'-bNot' = [pscustomobject] @{ Name = '-bNot'; FriendlyName = 'bitwise complement'; Topic = 'about_Arithmetic_Operators'; Category = 'Bitwise' }
# about_Assignment_Operators
'=' = [pscustomobject] @{ Name = '='; FriendlyName = 'assignment'; Topic = 'about_Assignment_Operators'; Category = 'Assignment' }
'+=' = [pscustomobject] @{ Name = '+='; FriendlyName = 'compound assignment'; Topic = 'about_Assignment_Operators'; Category = 'Assignment' }
'-=' = [pscustomobject] @{ Name = '-='; FriendlyName = 'compound assignment'; Topic = 'about_Assignment_Operators'; Category = 'Assignment' }
'*=' = [pscustomobject] @{ Name = '*='; FriendlyName = 'compound assignment'; Topic = 'about_Assignment_Operators'; Category = 'Assignment' }
'/=' = [pscustomobject] @{ Name = '/='; FriendlyName = 'compound assignment'; Topic = 'about_Assignment_Operators'; Category = 'Assignment' }
'%=' = [pscustomobject] @{ Name = '%='; FriendlyName = 'compound assignment'; Topic = 'about_Assignment_Operators'; Category = 'Assignment' }
'++' = [pscustomobject] @{ Name = '++'; FriendlyName = 'increment'; Topic = 'about_Assignment_Operators'; Category = 'Assignment' }
'--' = [pscustomobject] @{ Name
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