Creating an Open File Dialog in PowerShell

Function Open-FileDialog {
	<#
        .SYNOPSIS
        Creates an Open File Dialog.

        .DESCRIPTION
        Creates an Open File Dialog.
        Takes a custom filter for file extentions as well as starting in a different directory.

        .PARAMETER Filter
        Specifies the file extention filter. Defaults to Documents (*.docx) and SpreadSheets (*.xlsx)

        .PARAMETER InitialDirectory
        Specifies the initial directory. "Desktop" is the default.
		
		.PARAMETER Title
        Specifies the title of the open file dialog box.
		
		.PARAMETER Multiselect
        Specifies if multi file select is enabled. False is the default.

        .INPUTS
        None. You cannot pipe objects to Open-FileDialog.

        .OUTPUTS
        System.Windows.Forms.OpenFileDialog. Open-FileDialog returns a string with the extension or file name.

        .EXAMPLE
        PS> $file = Open-FileDialog
		PS> $file.FileName
        C:\Temp\File.txt
		
		.EXAMPLE
        PS> $file = Open-FileDialog -Title "My Title"
		PS> $file.FileName
        C:\Temp\File.txt
		
		.EXAMPLE
        PS> $file = Open-FileDialog -Title "My Title" -Multiselect
		PS> $file.FileNames
        {C:\Temp\File.text,C:\Temp\File2.txt}
		
        .EXAMPLE
        PS> $csv = Import-CSV (Open-FileDialog -InitialDirectory "C:\Temp" -Filter "CSV|*.csv").FileName
        File.doc

        .LINK
        Online version: https://www.chriscolden.net/2023/03/20/creating-an-open-file-dialog-in-powershell/
    #>
	
	Param (
        [Parameter(Mandatory=$false)] [String]$Filter = 'Documents (*.docx)|*.docx|SpreadSheet (*.xlsx)|*.xlsx',
		[Parameter(Mandatory=$false)] [String]$InitialDirectory = [Environment]::GetFolderPath('Desktop'),
		[Parameter(Mandatory=$false)] [String]$Title = $null,
		[Parameter(Mandatory=$false)] [Switch]$Multiselect = $false
    )
	
	if (-not ([System.AppDomain]::CurrentDomain.GetAssemblies() | ?{$_.Location -match "System.Windows.Forms"}))
	{
		Add-Type -AssemblyName System.Windows.Forms
	}
	
	$FileBrowser = New-Object System.Windows.Forms.OpenFileDialog -Property @{ 
		InitialDirectory = $InitialDirectory 
		Filter = $Filter
		Multiselect = $Multiselect
		Title = $Title
	}
	$null = $FileBrowser.ShowDialog()
	
	Return $FileBrowser
}