Public/Get-VcRedist.ps1

Function Get-VcRedist {
    <#
    .SYNOPSIS
        Downloads the Visual C++ Redistributables from an array returned by Get-VcXml.

    .DESCRIPTION
        Downloads the Visual C++ Redistributables from an array returned by Get-VcXml into a folder structure that represents release and processor architecture.
        If the redistributable exists in the specified path, it will not be re-downloaded.

    .OUTPUTS
         System.Array

    .NOTES
        Author: Aaron Parker
        Twitter: @stealthpuppy

    .LINK
        https://github.com/aaronparker/Install-VisualCRedistributables

    .PARAMETER VcList
        Sepcifies the array that lists the Visual C++ Redistributables to download

    .PARAMETER Path
        Specify a target folder to download the Redistributables to, otherwise use the current folder.

    .PARAMETER Release
        Specifies the release (or version) of the redistributables to download or install.

    .PARAMETER Architecture
        Specifies the processor architecture to download or install.

    .EXAMPLE
        Get-VcXml | Get-VcRedist -Path C:\Redist

        Description:
        Downloads the supported Visual C++ Redistributables to C:\Redist.
        
    .EXAMPLE
        Get-VcRedist -VcXml $VcRedists -Release "2012","2013",2017"

        Description:
        Downloads only the 2012, 2013 & 2017 releases of the Visual C++ Redistributables listed in $VcRedists

    .EXAMPLE
        Get-VcList | Get-VcRedist -Path C:\Temp\VcRedist -Architecture x64

        Description:
        Downloads only the 64-bit versions of the Visual C++ Redistributables listed in $VcRedists.
    #>

    [CmdletBinding(SupportsShouldProcess = $True)]
    [OutputType([Array])]
    Param (
        [Parameter(Mandatory = $True, Position = 0, ValueFromPipeline = $True, ValueFromPipelineByPropertyName = $False, `
                HelpMessage = ".")]
        [ValidateNotNull()]
        [array]$VcList,

        [Parameter(Mandatory = $False, Position = 1, HelpMessage = "Specify a target path to download the Redistributables to.")]
        [ValidateScript({ If (Test-Path $_ -PathType 'Container') { $True } Else { Throw "Cannot find path $_" } })]
        [string]$Path,

        [Parameter(Mandatory = $False, HelpMessage = "Specify the version of the Redistributables to download.")]
        [ValidateSet('2005', '2008', '2010', '2012', '2013', '2015', '2017')]
        [string[]]$Release = @("2008", "2010", "2012", "2013", "2015", "2017"),

        [Parameter(Mandatory = $False, HelpMessage = "Specify the processor architecture/s to download.")]
        [ValidateSet('x86', 'x64')]
        [string[]]$Architecture = @("x86", "x64")
    )
    Begin {
        $Output = @()
    }
    Process {

        # Filter release and architecture if specified
        If ( $PSBoundParameters.ContainsKey('Release') ) {
            Write-Verbose "Filtering releases for platform."
            $VcList = $VcList | Where-Object { $_.Release -eq $Release }
        }
        If ( $PSBoundParameters.ContainsKey('Architecture') ) {
            Write-Verbose "Filtering releases for architecture."
            $VcList = $VcList | Where-Object { $_.Architecture -eq $Architecture }
        }

        # Loop through each Redistributable and download to the target path
        ForEach ( $Vc in $VcList ) {
            Write-Verbose "Downloading: [$($Vc.Name)][$($Vc.Release)][$($Vc.Architecture)]"
            $Output += $Vc

            # Create the folder to store the downloaded file. Skip if it exists
            # $folder = "$($(Get-Item -Path $Path).FullName)\$($Vc.Release)\$($Vc.Architecture)\$($Vc.ShortName)"
            $folder = Join-Path (Join-Path (Join-Path $(Resolve-Path -Path $Path) $Vc.Release) $Vc.Architecture) $Vc.ShortName

            If ( Test-Path -Path $folder ) {
                Write-Verbose "Folder '$folder' exists. Skipping."
            }
            Else {
                If ( $pscmdlet.ShouldProcess($folder, "Create") ) {
                    New-Item -Path $folder -Type Directory -Force -ErrorAction SilentlyContinue | Out-Null
                }
            }

            # If the target Redistributable is already downloaded, skip it.
            # If running on Windows PowerShell use Start-BitsTransfer, otherwise use Invoke-WebRequest
            $target = Join-Path $folder $(Split-Path -Path $Vc.Download -Leaf)
            Write-Verbose "Target is $($target)"
            If ( Test-Path -Path $target -PathType Leaf ) {
                Write-Verbose "$($target) exists. Skipping."
            }
            Else {
                If ( Get-Command Start-BitsTransfer -ErrorAction SilentlyContinue ) {
                    If ( $pscmdlet.ShouldProcess($Vc.Download, "BitsDownload") ) {
                        Start-BitsTransfer -Source $Vc.Download -Destination $target `
                            -Priority High -ErrorAction Continue -ErrorVariable $ErrorBits `
                            -DisplayName "Visual C++ Redistributable Download" -Description $Vc.Name
                    }
                }
                Else {
                    If ( $pscmdlet.ShouldProcess($Vc.Download, "WebDownload") ) {
                        Invoke-WebRequest -Uri $Vc.Download -OutFile $target
                    }
                }
            }
        }
    }
    End {
        # Return the $VcList array on the pipeline so that we can act on what was downloaded
        $Output
    }
}