XAML form + Cancel button response - xaml

Question

I am working on my first form in Powershell and am using XAML (built on the code from https://foxdeploy.com/2015/04/10/part-i-creating-powershell-guis-in-minutes-using-visual-studio-a-new-hope/).
The form works great so now I'm working on data validation. I am trying to make all of the fields mandatory through a While loop, but I can't break out of it. How would I take the code below and make it understand when someone clicks the Cancel button, that it should exit the loop? I tried checking $WPFcancelButton.IsPressed, but that doesn't seem to be getting updated.
Thanks.
Function Get-HubNameFields {
$inputXML = #"
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:WpfApplication1"
mc:Ignorable="d"
Title="Naming Tool" Height="350" Width="525">
<Grid Margin="0,0,-8,0" HorizontalAlignment="Left" Width="525">
<TextBlock x:Name="textBlock" Margin="10,10,145.907,0" TextWrapping="Wrap" Text="Define the parameters of a name" VerticalAlignment="Top" Height="17.945"/>
<Label x:Name="custLongNameLabel" Content="Customer Long Name" HorizontalAlignment="Left" Margin="10,32.945,0,0" VerticalAlignment="Top"/>
<TextBox x:Name="custLongNameTxt" Height="21.96" Margin="141.003,36.945,224.239,0" TextWrapping="Wrap" VerticalAlignment="Top" ToolTip="Full name of the customer."/>
<Label x:Name="custShortNameLabel" Content="Customer Short Name" HorizontalAlignment="Left" Margin="10,59.905,0,0" VerticalAlignment="Top"/>
<TextBox x:Name="custShortNameTxt" Height="21.96" Margin="141.003,63.905,224.239,0" TextWrapping="Wrap" VerticalAlignment="Top" ToolTip="Abreviation of the customer's name."/>
<Label x:Name="siteLongNameLabel" Content="Site Long Name" HorizontalAlignment="Left" Margin="10,86.865,0,0" VerticalAlignment="Top"/>
<TextBox x:Name="siteLongNameTxt" Height="21.96" Margin="141.003,90.865,224.239,0" TextWrapping="Wrap" VerticalAlignment="Top" ToolTip="Full name of the site."/>
<Label x:Name="siteShortNameLabel" Content="Site Short Name" HorizontalAlignment="Left" Margin="10,113.785,0,0" VerticalAlignment="Top"/>
<TextBox x:Name="siteShortNameTxt" Height="21.96" Margin="141.003,117.825,224.239,0" TextWrapping="Wrap" VerticalAlignment="Top" ToolTip="Abbreviation of the site's name."/>
<Label x:Name="hubNumberLabel" Content="Hub Number" HorizontalAlignment="Left" Margin="10,140.825,0,0" VerticalAlignment="Top"/>
<TextBox x:Name="hubNumberTxt" Height="21.96" Margin="141.003,144.785,224.239,0" TextWrapping="Wrap" VerticalAlignment="Top" ToolTip="Number of the Hub."/>
<RadioButton x:Name="radioButton" Content="Data Center Hub" HorizontalAlignment="Left" Margin="10,0,0,122.611" VerticalAlignment="Bottom"/>
<RadioButton x:Name="radioButton1" Content="Office/Other" HorizontalAlignment="Left" Margin="10,0,0,102.651" VerticalAlignment="Bottom"/>
<Button x:Name="okButton" Content="OK" HorizontalAlignment="Left" Margin="18.928,0,0,10" VerticalAlignment="Bottom" Width="50" IsDefault="True"/>
<Button x:Name="cancelButton" Content="Cancel" HorizontalAlignment="Left" Margin="80.317,0,0,10" VerticalAlignment="Bottom" Width="50" IsCancel="True"/>
</Grid>
</Window>
"#
$inputXML = $inputXML -replace 'mc:Ignorable="d"','' -replace "x:N",'N' -replace '^<Win.*', '<Window'
[void][System.Reflection.Assembly]::LoadWithPartialName('PresentationFramework')
[xml]$XAML = $inputXML
#Read XAML
$reader = (New-Object System.Xml.XmlNodeReader $xaml)
Try {
$form = [Windows.Markup.XamlReader]::Load($reader)
}
Catch {
Write-Host "Unable to load Windows.Markup.XamlReader. Double-check syntax and ensure .Net is installed."
}
#This line takes the XAML data, adds "WPF" to the front of each XML node name, and creates a global variable.
$xaml.SelectNodes("//*[#Name]") | Foreach {Set-Variable -Name "WPF$($_.Name)" -Value $Form.FindName($_.Name) -Scope Global}
<#Only need this function and its call if you don't know the name of the variables that the function generates from the XML.
Function Get-FormVariables {
If ($global:ReadmeDisplay -ne $true) {
Write-host "If you need to reference this display again, run Get-FormVariables" -ForegroundColor Yellow;$global:ReadmeDisplay=$true
}
Write-host "Found the following interactable elements from our form" -ForegroundColor Cyan
Get-Variable WPF*
}
Get-FormVariables#>
#Specify what the OK button should do, when clicked.
$WPFokButton.Add_Click({$form.Close()})
#Now that the form is built, show it, surpressing other messages.
$form.ShowDialog() | Out-Null
}
#Initialize some local variables.
$hubType = $null
$TextInfo = (Get-Culture).TextInfo
While ((($customerLongName.Length -eq 0) -or ($customerShortName.Length -eq 0) -or ($siteLongName.Length -eq 0) -or ($siteShortName.Length -eq 0) -or ($hubType -eq $null)) -or ($WPFcancelButton.IsPressed -like "false*")) {
Write-Host "the cancel button value is $($WPFcancelButton.ispressed)"
Get-HubNameFields
$customerLongName = $WPFcustLongNameTxt.Text
$customerLongName = $TextInfo.ToTitleCase($customerLongName.ToLower())
$customerLongName = $customerLongName -replace '\s',''
$customerShortName = ($WPFcustShortNameTxt.Text).ToLower()
$customerShortName = $customerShortName -replace '\s',''
$siteLongName = $WPFsiteLongNameTxt.Text
$siteLongName = $TextInfo.ToTitleCase($siteLongName.ToLower())
$siteLongName = $siteLongName -replace '\s',''
$siteShortName = ($WPFsiteShortNameTxt.Text).ToLower()
$siteShortName = $siteShortName -replace '\s',''
If ($WPFradioButton.IsChecked -eq $true) {
$hubType = 'dh'
}
If ($WPFradioButton1.IsChecked -eq $true) {
$hubType = 'ch'
}
}

Answer 1

I added an event handler, to set a variable, and broke the loop based on that.
$WPFcancelButton.Add_Click({Set-Variable -Name UserCancelled -Value $true -Scope Global})