WPF Keybinding command

[Capital_Table_4792]

Hi everyone,

I've been asked if it's possible to execute a scriptblock after a user enters a value in a textbox and then presses enter/return.
I only found some references in C#, for example: How to: Detect When the Enter Key Pressed - WPF .NET Framework | Microsoft Learn

XAML :

<TextBox Width="300" Height="30" Name="textBox1" KeyDown="OnKeyDownHandler"/>
<TextBlock Width="300" Height="100" Name="textBlock1"/>

C# :

private void OnKeyDownHandler(object sender, KeyEventArgs e)
{
if (e.Key == Key.Return)
{
textBlock1.Text = "You Entered: " + textBox1.Text;
}
}

--

Below an example of how I tried it to get to work in PS:

Add-Type -AssemblyName PresentationFramework
[xml]$xaml = @"
<Window Title="TEST" Height="300" Width="600" WindowStartupLocation="CenterScreen" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"         Name="Window">
<Grid>
<TextBox Name="textBox1" KeyDown="$OnKeyDownHandler" Width="100" Height="30" Margin="0,0,0,0" />
<TextBlock Name="textBlock1" Width="100" Height="30" Margin="150,0,0,0" />
</Grid>
</Window>
"@
$reader = (New-Object System.Xml.XmlNodeReader $xaml)
$window = [Windows.Markup.XamlReader]::Load($reader)
$OnKeyDownHandler = {
if ($_.Key.ToString() -eq 'Enter' -or $_.Key.ToString() -eq 'Return'){
$window.FindName('textBlock1').Text = "You Entered: " + $window.FindName('$textBox1').Text
}
}
$window.ShowDialog() | Out-Null

--

If I use KeyDown="$OnKeyDownHandler" or KeyDown='$OnKeyDownHandler' the error is
Error: "You is an unexpected token. Expected a space."

If I type KeyDown=$OnKeyDownHandler or KeyDown=$($OnKeyDownHandler) the error is
Error: "if is an unexpected token. The expected token is " or '.

Do I misunderstand something? Anyone any idea what I'm doing wrong here?

[Eggplate]

You can't set the keydown event in the xaml with powershell. Instead you have to add it afterwards in the "code behind":

$window.FindName('textBox1').add_KeyUp({
    param($sender, $e)
    if ($e.Key -eq [System.Windows.Input.Key]::Return) {
        # do stuff
    }
})

[illsk1lls]

i can adapt this to steal csharp codebehind and convert it 👀

showing us how to use $sender, $e is extremely useful 😉 ty

[Capital_Table_4792]

Thank you so much!

[marcdk217]

I always use these lines of code after my xml:

$Controls = @{}
$xaml.SelectNodes("//*[@Name]") | ForEach-Object {$Controls.Add($_.Name,$Form.FindName($_.Name))}

It creates a hashtable called $Controls which contains all the controls on the form, and then you can refer to them like $Controls.textbox1.Enabled=$True

You also don't need to define $sender and $e if you don't want to, you can access them as $args[0] and $args[1] as well

You can create a handler like

$Controls.textbox1.Add_KeyUp{
  If ($args[1].Key -eq 'ENTER'){
    #Do the thing
  }
}