Option Menu in Powershell: Continue After Loop - powershell

Question

I would like to create a simple menu in powershell. If you look at my example bellow, I am waiting in do loop until the key 'q' is pressed. If user hits '1' or '2', it should do something specified in switch, leave the loop and continue in script by showing "Another part of code".
If break is used in switch, it doesn't leave the loop. If return is is used, the entire script is exited.
Here's the code:
function Select-Machine
{
cls
Write-Host "1: Option1"
Write-Host "2: Option2"
Write-Host
}
Do{
Select-Machine
$input = Read-Host "Choose Virtual Machine"
switch ($input)
{
'1' {
#1: Do Something
break
}
'2' {
#2: Do Something
break
}
}
}until($input -eq 'q')
Write-Host "Another part of code"

Answer 1

When you use the break statement within a switch you only exit the switch (e.g it doesn't attempt to evaluate any of the other options). You could instead replace where you have break with $input = 'q' and this will result in the loop then completing.
Alternatively you could have an if after the switch to check a list of valid options and do a break at that point, which would then operate on the loop. E.g:
if ($input -in '1','2') { break }

Answer 2

What I would do is use a Do/While loop instead of a Do/Until loop. Also, move the switch outside of the loop, there's no need to have it in there.
Do{
Select-Machine
$Response = Read-Host "Choose Virtual Machine"
}While($Response -notin 1,2,'q')
Switch($Response){
1 {
#Do 1 stuff!
continue
}
2 {
#Do 2 stuff!
continue
}
}
I've done this a number of times in scripts that I know are going to be interactive and have a menu for options. Towards that end I even wrote a function to make decent looking menus for me:
Function MenuMaker{
param(
[parameter(Mandatory=$true)][String[]]$Selections,
[switch]$IncludeExit,
[string]$Title = $null
)
$Width = if($Title){$Length = $Title.Length;$Length2 = $Selections|%{$_.length}|Sort -Descending|Select -First 1;$Length2,$Length|Sort -Descending|Select -First 1}else{$Selections|%{$_.length}|Sort -Descending|Select -First 1}
$Buffer = if(($Width*1.5) -gt 78){[math]::floor((78-$width)/2)}else{[math]::floor($width/4)}
if($Buffer -gt 6){$Buffer = 6}
$MaxWidth = $Buffer*2+$Width+$($Selections.count).length+2
$Menu = #()
$Menu += "╔"+"═"*$maxwidth+"╗"
if($Title){
$Menu += "║"+" "*[Math]::Floor(($maxwidth-$title.Length)/2)+$Title+" "*[Math]::Ceiling(($maxwidth-$title.Length)/2)+"║"
$Menu += "╟"+"─"*$maxwidth+"╢"
}
For($i=1;$i -le $Selections.count;$i++){
$Item = "$(if ($Selections.count -gt 9 -and $i -lt 10){" "})$i`. "
$Menu += "║"+" "*$Buffer+$Item+$Selections[$i-1]+" "*($MaxWidth-$Buffer-$Item.Length-$Selections[$i-1].Length)+"║"
}
If($IncludeExit){
$Menu += "║"+" "*$MaxWidth+"║"
$Menu += "║"+" "*$Buffer+"X - Exit"+" "*($MaxWidth-$Buffer-8)+"║"
}
$Menu += "╚"+"═"*$maxwidth+"╝"
$menu
}
Then I can just call it like:
MenuMaker -Selections 'SQL Server','Exchange Server' -Title 'Choose Virtual Machine' -IncludeExit
And it will spit back:
╔═══════════════════════════════════╗
║ Choose Virtual Machine ║
╟───────────────────────────────────╢
║ 1. SQL Server ║
║ 2. Exchange Server ║
║ ║
║ X - Exit ║
╚═══════════════════════════════════╝
To put that in context to your code, and my suggestions, it would look like:
Do{
cls
MenuMaker -Selections 'SQL Server','Exchange Server' -Title 'Choose Virtual Machine' -IncludeExit
$Response = Read-Host "Choose Virtual Machine"
}While($Response -notin 1,2,'x')
Edit: I just realized that my while vs until argument is pointless, all it does is flip the -in to -notin. The point is that you need to validate their response against the possible options, not just against 'q'.

Answer 3

You can use labels with break to jump out from the outer loop. I don't think it's especially beautiful, much better is to turn until condition true. But here we go. Oh, and please don't use $input variable name, that's PowerShell's automatic variable reserved for, em, input.
Write-Host "Begin"
:menu Do {
$i = Read-Host "Select"
switch ($i) {
'1' {
write-host "Do 1"
break menu
}
'2' {
write-host "Do 2"
break menu
}
}
} until($i -eq 'q')
Write-Host "End"

Answer 4

I think you can simplify this a bit and remove the function:
Do{
#Select-Machine
write-Host "input 1 or 2 - Choose Virtual Machine"
if ($input = Read-Host "type in 1 or 2"){
switch ($input)
{
'1' {
#1: Do Something
Write-host '1 doing something'
break
}
'2' {
#2: Do Something
write-host '2 doing something'
break
}
}}
}until($input -eq 'q')
Write-Host "Another part of code"