Private/Get-FileName.ps1

Function Get-FileName($initialDirectory) {
    [System.Reflection.Assembly]::LoadWithPartialName("System.windows.forms") | Out-Null
    $OpenFileDialog = New-Object System.Windows.Forms.OpenFileDialog
    $OpenFileDialog.initialDirectory = $initialDirectory
    $OpenFileDialog.filter = "CSV files (*.csv, *.txt)|*.csv;*.txt| All files *.*|*.*"
    $OpenFileDialog.ShowDialog() | Out-Null
    $OpenFileDialog.filename
} #end function Get-FileName