PowerShell
Parametersätze

Einführung

Einfache Parametersätze

function myFunction
{
    param(
        # If parameter 'a' is used, then 'c' is mandatory
        # If parameter 'b' is used, then 'c' is optional, but allowed
        # You can use parameter 'c' in combination with either 'a' or 'b'
        # 'a' and 'b' cannot be used together

        [parameter(ParameterSetName="AandC", mandatory=$true)]
        [switch]$a,
        [parameter(ParameterSetName="BandC", mandatory=$true)]
        [switch]$b,
        [parameter(ParameterSetName="AandC", mandatory=$true)]
        [parameter(ParameterSetName="BandC", mandatory=$false)]
        [switch]$c
    )
    # $PSCmdlet.ParameterSetName can be used to check which parameter set was used
    Write-Host $PSCmdlet.ParameterSetName
}

# Valid syntaxes
myFunction -a -c
# => "Parameter set : AandC"
myFunction -b -c
# => "Parameter set : BandC"
myFunction -b
# => "Parameter set : BandC"

# Invalid syntaxes
myFunction -a -b
# => "Parameter set cannot be resolved using the specified named parameters."
myFunction -a
# => "Supply values for the following parameters:
#    c:"

Parametersatz, um die Verwendung eines Parmeters zu erzwingen, wenn ein anderer ausgewählt wird.

Wenn Sie beispielsweise die Verwendung des Parameters Kennwort erzwingen möchten, wenn der Parameter Benutzer angegeben wird. (und umgekehrt)

Function Do-Something
{
    Param
    (
        [Parameter(Mandatory=$true)]
        [String]$SomeThingToDo,
        [Parameter(ParameterSetName="Credentials", mandatory=$false)]
        [String]$Computername = "LocalHost",
        [Parameter(ParameterSetName="Credentials", mandatory=$true)]
        [String]$User,
        [Parameter(ParameterSetName="Credentials", mandatory=$true)]
        [SecureString]$Password
    )

    #Do something
}

# This will not work he will ask for user and password
Do-Something -SomeThingToDo 'get-help about_Functions_Advanced' -ComputerName

# This will not work he will ask for password
Do-Something -SomeThingToDo 'get-help about_Functions_Advanced' -User

Parametersatz zur Begrenzung der Kombination von Parmetern

Function Do-Something
{
    Param
    (
        [Parameter(Mandatory=$true)]
        [String]$SomeThingToDo,
        [Parameter(ParameterSetName="Silently", mandatory=$false)]
        [Switch]$Silently,
        [Parameter(ParameterSetName="Loudly", mandatory=$false)]
        [Switch]$Loudly
    )

    #Do something
}

# This will not work because you can not use the combination Silently and Loudly
Do-Something -SomeThingToDo 'get-help about_Functions_Advanced' -Silently -Loudly