Folder Picker not loading outside ISE - powershell

Question

I have a script that starts with a folder picker dialog, however I understand that POSH can't execute scripts outside of ISE like that (STA vs. MTA), so I have a separate script to dot-source it.
I have error handling in the first script in case the user presses Cancel:
if ($Show -eq "OK") {
return $objForm.SelectedPath
} else {
Write-Error "Operation cancelled by user."
exit
}
Now I need for the 2nd script (the one calling the first script) to detect the same Cancellation.
This is what I've got so far:
"Choose a folder containing the items to be moved..."
""
try {
powershell -STA -File "C:\Test\Script.ps1"
""
"Operation completed. An event log has been created:"
(Resolve-Path .\).Path +"\log.txt"
""
"Press any key to continue..."
""
$x = $Host.UI.RawUI.ReadKey("NoEcho,IncludeKeyDown")
} catch {
if ($LastExitCode -ne 0) { exit $LastExitCode }
Write-Host "User cancelled the operation."
""
"Press any key to continue..."
""
$x = $Host.UI.RawUI.ReadKey("NoEcho,IncludeKeyDown")
}
That gives me a nasty looking multi-line Write Error Exception in red text.
At C:\Test\Script.ps1:27 char:30
+ $folder = Select-FolderDialog <<<< #contains user's selected folder
+ CategoryInfo : NotSpecified: (:) [Write-Error], WriteErrorException
+ FullyQualifiedErrorId : Microsoft.PowerShell.Commands.WriteErrorException,Select-FolderDialog
I'm not sure why it's generating an error message referencing the other script, since the other script runs fine (from ISE of course).
Desired Output:
If user cancels folder picker, I just want a nice clean error message to display:
User cancelled the operation.
Press any key to continue.
Edit
Here is the folder picker script I have. It works fine in ISE but when you Right Click and choose Run with Powershell it just launches a blank prompt window. To prevent the end user from accidentally editing the script I would like for it to run from outside ISE. BTW, I am using POSH 2.
# Function for folder picker dialog
Function Select-FolderDialog
{
[System.Reflection.Assembly]::LoadWithPartialName("System.windows.forms") | Out-Null
$objForm = New-Object System.Windows.Forms.FolderBrowserDialog
# Default location is script's location
$objForm.SelectedPath = (Resolve-Path .\).Path
$objForm.Description = "Select Folder"
$Show = $objForm.ShowDialog()
If ($Show -eq "OK")
{Return $objForm.SelectedPath}
Else
{
Write-Error "Operation cancelled by user."
Exit
}
}
$folder = Select-FolderDialog #contains user's selected folder

Answer 1

Keep just your function in your 2nd script, dot source the file to load the function, then place the $folder = Select-FolderDialog call in your main script, a la:
"Choose a folder containing the items to be moved..."
""
try {
. "C:\Test\Script.ps1" # this dot sources the function from the second file (no need to call a separate Powershell process to do this, as data from that process won't be returned to the primary process calling it)
$folder = Select-FolderDialog # this runs the function in your original script, storing the result in the $folder variable
""
"Operation completed. An event log has been created:"
(Resolve-Path .\).Path +"\log.txt"
""
"Press any key to continue..."
""
$x = $Host.UI.RawUI.ReadKey("NoEcho,IncludeKeyDown")
} catch {
if ($LastExitCode -ne 0) { exit $LastExitCode }
Write-Host "User cancelled the operation."
""
"Press any key to continue..."
""
$x = $Host.UI.RawUI.ReadKey("NoEcho,IncludeKeyDown")
}