Using ValidateSet in dynamic parameter

Question

This is in continuation to one question I asked earlier on this site. There are two issues:

1. The moment I add any function below last line of this code in the script file, I start getting compilation error. (Any code/function written after last line will show compilation error)

-AND-

2. I need to extend the parameters to add validate set in dynamic parameters. When I try below code, the validate set added is applying to all the parameters and giving error. Whereas, I want the validate set to apply only on 'Workday' parameter.

3. Also, need to add support for accepting values from pipeline and accepting values from pipeline by property names to these parameters (except [Switch] parameters)

Here is the code:

[CmdletBinding(DefaultParameterSetName='DefaultConfiguration')]
Param(
    [Parameter(Mandatory=$True, ValueFromPipeline=$True, ValueFromPipelineByPropertyName=$True)]
    [String]$ResourceGroupName,
    [Parameter(Mandatory=$True, ValueFromPipeline=$True, ValueFromPipelineByPropertyName=$True)]
    [String]$VaultName,

    [Parameter(Mandatory=$True, ValueFromPipeline=$True, ValueFromPipelineByPropertyName=$True)]
    [String]$SubscriptionID,

    [Parameter(Mandatory=$True, ValueFromPipeline=$True, ValueFromPipelineByPropertyName=$True)]
    [String]$Location,

    [Switch]$CustomizeDPMSubscriptionSettings,
    [Switch]$SetEncryption,
    [Switch]$SetProxy,
    [Switch]$SetThrottling
)

DynamicParam {
    $paramDictionary = New-Object -Type System.Management.Automation.RuntimeDefinedParameterDictionary
    $attributes = New-Object System.Management.Automation.ParameterAttribute
    $attributes.ParameterSetName = "__AllParameterSets"
    $attributes.Mandatory = $true
    $attributeCollection = New-Object -Type System.Collections.ObjectModel.Collection[System.Attribute]
    $attributeCollection.Add($attributes)

    # If "-CustomizeDPMSubscriptionSettings" is used, then add the "StagingAreaPath" parameter
    if ($CustomizeDPMSubscriptionSettings) {
        $dynParam1 = New-Object -Type System.Management.Automation.RuntimeDefinedParameter("StagingAreaPath", [String], $attributeCollection)   
        $paramDictionary.Add("StagingAreaPath", $dynParam1)

        # If "-SetEncryption" is used, then add the "EncryptionPassPhrase" parameter
        if ($SetEncryption) { 
            $dynParam1 = New-Object -Type System.Management.Automation.RuntimeDefinedParameter("EncryptionPassPhrase", [String], $attributeCollection)   
            $paramDictionary.Add("EncryptionPassPhrase", $dynParam1)
        }

        # If "-SetProxy" is used, then add the "ProxyServerAddress" "ProxyServerPort" and parameters
        if ($SetProxy) {
            $dynParam1 = New-Object -Type System.Management.Automation.RuntimeDefinedParameter("ProxyServerAddress", [String], $attributeCollection)   
            $paramDictionary.Add("ProxyServerAddress", $dynParam1)
            $dynParam2 = New-Object -Type System.Management.Automation.RuntimeDefinedParameter("ProxyServerPort", [Int32], $attributeCollection)   
            $paramDictionary.Add("ProxyServerPort", $dynParam2)
        }
        if ($SetThrottling) {
            $dynParam1 = New-Object -Type System.Management.Automation.RuntimeDefinedParameter("ThrottlingStartWorkHour", [Int32], $attributeCollection)   
            $paramDictionary.Add("ThrottlingStartWorkHour", $dynParam1)
            $dynParam2 = New-Object -Type System.Management.Automation.RuntimeDefinedParameter("ThrottlingEndWorkHour", [Int32], $attributeCollection)   
            $paramDictionary.Add("ThrottlingEndWorkHour", $dynParam2)
            $dynParam3 = New-Object -Type System.Management.Automation.RuntimeDefinedParameter("ThrottlingWorkHourBandwidth", [Long], $attributeCollection)   
            $paramDictionary.Add("ThrottlingWorkHourBandwidth", $dynParam3)
            $dynParam4 = New-Object -Type System.Management.Automation.RuntimeDefinedParameter("ThrottlingNonWorkHourBandwidth", [Long], $attributeCollection)   
            $paramDictionary.Add("ThrottlingNonWorkHourBandwidth", $dynParam4)

            $_Days = @("Su","Mo","Tu","We","Th","Fr","Sa")
            $ValidateSet = New-Object System.Management.Automation.ValidateSetAttribute($_Days)
            $dynParam5 = New-Object -Type System.Management.Automation.RuntimeDefinedParameter("Workday", [System.DayofWeek], $attributeCollection)
            $dynParam5.Attributes.Add($ValidateSet) 
            $paramDictionary.Add("Workday", $dynParam5)
        }
    }
    return $paramDictionary
}

Process {
    foreach ($key in $PSBoundParameters.keys) {
        Set-Variable -Name $key -Value $PSBoundParameters."$key" -Scope 0
    }
}

Answer 1

Thanks to @PetSerAl for his suggestions and inputs. We can't place code/function outside of Begin/Process/End block when they are present.