# Note: store in your profile for easy use
# Example use:
# $file = Select-FileDialog -Title "Select a file" -Directory "D:\scripts" -Filter "Powershell Scripts|(*.ps1)"

function Select-FileDialog
{
	param([string]$Title,[string]$Directory,[string]$Filter="All Files (*.*)|*.*")
	[System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms") | Out-Null
	$objForm = New-Object System.Windows.Forms.OpenFileDialog
	$objForm.InitialDirectory = $Directory
	$objForm.Filter = $Filter
	$objForm.Title = $Title
	$Show = $objForm.ShowDialog()
	If ($Show -eq "OK")
	{
		Return $objForm.FileName
	}
	Else
	{
		Write-Error "Operation cancelled by user."
	}
}

$file = Select-FileDialog -Title "Select a file" -Directory "D:\scripts" -Filter "Powershell Scripts (*.ps1)|*.ps1"

#multiple file category arguments should not include extra space:
#-Filter “Text files (*.txt) | *.txt | All files (*.*) | *.*”
#does not work — only show *.* filter.
#-Filter “Text files (*.txt)|*.txt|All files (*.*)|*.*”
#works.