Powershell + XAML + Search Box + capture and display - powershell

Question

I am just about finished with program and need some help getting over the finish line. What is supposed to do is search through log files in a predefined directory. Nothing happens with the text I enter in the search box nor when I use the button that I created to execute the search. I have searched all over the Internet which has me as far as I am. I see lot's of examples in Winforms but I don't know the "translation" between Winforms and WPF.
I think that if someone can get me passed this hurdle I can implement the other features I want to add.
PS: I really have no programming skills, just tenacity.
Thanks in advance to all who help.
'''
# Import needed Assemblies
Add-Type -AssemblyName PresentationCore, PresentationFramework, WindowsBase,
System.Drawing, System.Windows.Forms, WindowsFormsIntegration
[void][System.Reflection.Assembly]::LoadWithPartialName('PresentationFramework')
[Windows.Forms.Application]::EnableVisualStyles()
#XAML form designed using Visual Studio
# Build the GUI
[xml]$Form = #"
<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Log Crawler"
HorizontalAlignment="Center"
FontSize="11" Height="700" Width="1300" FontFamily="Calibri"
WindowStartupLocation="CenterScreen"
ScrollViewer.HorizontalScrollBarVisibility="Disabled"
ScrollViewer.VerticalScrollBarVisibility="Disabled" WindowStyle="ThreeDBorderWindow">
<Grid Margin="0,0,0,0">
<Grid.Background>
<LinearGradientBrush EndPoint="0.8,1" StartPoint="0.8,0">
<GradientStop Color="Black"/>
<GradientStop Color="White" Offset="1"/>
</LinearGradientBrush>
</Grid.Background>
<TextBox x:Name="IntegrationsLogCrawler" Text="Integration Log Crawler"
HorizontalAlignment="Center" VerticalAlignment="Top" TextAlignment="Center" TextWrapping="NoWrap"
Margin="0,20,0,0 " Height="37" Width="260"
FontSize="24" FontFamily="Calibri" FontWeight="Bold" FontStyle="Normal" FlowDirection="LeftToRight"/>
<GroupBox x:Name="SearchBox" Header="SearchBox"
HorizontalAlignment="Center" VerticalAlignment="Top"
FontSize="12" FontFamily="Calibri" FontWeight="Bold" Foreground="#FFE4E41A"
Margin="0,100,0,0" Height="40" Width="400">
<TextBox x:Name="InputBox" TextWrapping="NoWrap"/>
</GroupBox>
<Button x:Name="LogCrawl" Content="Log Crawl"
HorizontalAlignment="Center" VerticalAlignment="Top"
Margin="0,150,0,0" Height="40" Width="190"
FontSize="18" FontFamily="Calibri" FontWeight="Bold" Foreground="#FFEE0C3F"/>
<Button x:Name="Exit" Content="Exit"
HorizontalAlignment="Center" VerticalAlignment="Top"
Margin="0,200,0,0" Height="39" Width="110"
FontSize="16" FontFamily="Calibri" FontWeight="Bold" Foreground="#FFE4E41A" Background="#FF040404"/>
<GroupBox x:Name="Results" Header="Results"
HorizontalAlignment="Center" VerticalAlignment="Top"
FontSize="12" FontFamily="Calibri" FontWeight="Bold" Foreground="#FFE4E41A"
Margin="0,250,0,0 " Height="250" Width="1000">
<TextBox x:Name="OutputBox" HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto"/>
</GroupBox>
</Grid>
</Window>
"#
#Create a form
$XMLReader = (New-Object System.Xml.XmlNodeReader $Form)
$XMLForm = [Windows.Markup.XamlReader]::Load($XMLReader)
#Connect to Controls
$xaml.SelectNodes("//*[#*[contains(translate(name(.),'n','N'),'Name')]]") | ForEach {
New-Variable -Name $_.Name -Value $XMLForm.FindName($_.Name) -Force
}
# Load Log Crawl Menu Button Controls
$InputBox = $XMLForm.FindName('InputBox')
$OutputBox = $XMLForm.FindName('OutputBox')
$LogCrawl = $XMLForm.FindName('LogCrawl')
$Exit = $XMLForm.FindName('Exit')
# Logfile Location
$LogFiles = "$($ENV:USERPROFILE)\Documents\_data\logfiles"
# Log Crawl Button Action
$LogCrawl1.Add_Click({
Select-String -Path "$LogFiles\*.*" -Pattern $InputBox -Context 10, 20 | Write-Host
})
# EXIT
$Exit.Add_Click({
$XMLForm.Close()
})
#Show XMLform
$null = $XMLForm.ShowDialog()
'''

Answer 1

I'm not sure about the workings of this part (gave me exception "You cannot call a method on a null-valued expression.") :
#Connect to Controls
$xaml.SelectNodes("//*[#*[contains(translate(name(.),'n','N'),'Name')]]") | ForEach {
New-Variable -Name $_.Name -Value $XMLForm.FindName($_.Name) -Force
}
and I think you should remove it.
Then you made a typo in the button variable name $LogCrawl1 --> $LogCrawl, but also change the Add_Click() method to:
# Log Crawl Button Action
$LogCrawl.Add_Click({
# Logfile Location
$LogFiles = "$($ENV:USERPROFILE)\Documents\_data\logfiles"
$OutputBox.Text = Select-String -Path "$LogFiles\*.*" -Pattern $InputBox.Text -SimpleMatch -Context 10, 20
})
P.S. It is unclear if this is also in your real code, but the final closing "# for the XAML here-string must not have whitespace to the left.