PowerShell XAML - Get textbox text into variable - wpf

Question

I am writing an application in which I need to have a dialog box for user input. The problem I am having is getting the value from a textbox into a variable after the user clicks on the button.
[xml]$XAML_ConnectDialog = #"
<Window Name="Form_ConnectDialog"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Connect" Height="176" Width="328" ResizeMode="NoResize" ShowInTaskbar="False">
<Grid>
<Grid.Background>
<LinearGradientBrush EndPoint="0.5,1" MappingMode="RelativeToBoundingBox" StartPoint="0.5,0">
<GradientStop Color="#FFB4B4B4" Offset="1"/>
<GradientStop Color="White" Offset="0.603"/>
</LinearGradientBrush>
</Grid.Background>
<TextBlock TextWrapping="Wrap" Text="Enter the hostname or IP address of the remote host to connect to." Margin="10,0,10,91"/>
<Label Content="Connect To:" HorizontalAlignment="Left" Height="27" VerticalAlignment="Top" Width="76" Margin="10,47,0,0"/>
<Button Name="Btn_ConnectDialog_Connect" Content="Connect" Height="20" Margin="194,88,26,20" IsDefault="True"/>
<TextBox Name="Txt_ConnectDialog_Input" HorizontalAlignment="Left" Height="23" Margin="91,51,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="208"/>
</Grid>
</Window>
"#
$XML_Node_Reader_ConnectDialog = (New-Object System.Xml.XmlNodeReader $XAML_ConnectDialog)
$ConnectDialog = [Windows.Markup.XamlReader]::Load($XML_Node_Reader_ConnectDialog)
$Btn_ConnectDialog_Connect = $ConnectDialog.FindName('Btn_ConnectDialog_Connect')
$Txt_ConnectDialog_Input = $ConnectDialog.FindName('Txt_ConnectDialog_Input')
$Btn_ConnectDialog_Connect.Add_Click({
$ConnectDialog.Hide()
$var = $Txt_ConnectDialog_Input.Text.ToString()
})
write-host $var
$ConnectDialog.ShowDialog() | Out-Null
Any help is appreciated.
Thanks

Answer 1

You're using Write-Host $var BEFORE you run the GUI. And since the GUI is used to define the variable in the first place, your Write-Host command will never return anything.
$var is not defined before your click-eventhandler. The eventhandler is a function, so the variable will be created in a local scope that only exists inside the function, and then deleted after the function/eventhandler is done. I've fixed this by specifying the eventhandler to store the value in the variable $var in the script scope, so it will be available until the script is finished.
Fixed script:
[xml]$XAML_ConnectDialog = #"
<Window Name="Form_ConnectDialog"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Connect" Height="176" Width="328" ResizeMode="NoResize" ShowInTaskbar="False">
<Grid>
<Grid.Background>
<LinearGradientBrush EndPoint="0.5,1" MappingMode="RelativeToBoundingBox" StartPoint="0.5,0">
<GradientStop Color="#FFB4B4B4" Offset="1"/>
<GradientStop Color="White" Offset="0.603"/>
</LinearGradientBrush>
</Grid.Background>
<TextBlock TextWrapping="Wrap" Text="Enter the hostname or IP address of the remote host to connect to." Margin="10,0,10,91"/>
<Label Content="Connect To:" HorizontalAlignment="Left" Height="27" VerticalAlignment="Top" Width="76" Margin="10,47,0,0"/>
<Button Name="Btn_ConnectDialog_Connect" Content="Connect" Height="20" Margin="194,88,26,20" IsDefault="True"/>
<TextBox Name="Txt_ConnectDialog_Input" HorizontalAlignment="Left" Height="23" Margin="91,51,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="208"/>
</Grid>
</Window>
"#
$XML_Node_Reader_ConnectDialog = (New-Object System.Xml.XmlNodeReader $XAML_ConnectDialog)
$ConnectDialog = [Windows.Markup.XamlReader]::Load($XML_Node_Reader_ConnectDialog)
$Btn_ConnectDialog_Connect = $ConnectDialog.FindName('Btn_ConnectDialog_Connect')
$Txt_ConnectDialog_Input = $ConnectDialog.FindName('Txt_ConnectDialog_Input')
$Btn_ConnectDialog_Connect.Add_Click({
$ConnectDialog.Hide()
$script:var = $Txt_ConnectDialog_Input.Text.ToString()
})
$ConnectDialog.ShowDialog() | Out-Null
write-host $var