Error Windows.Markup.XamlReader Load

[kuznetcovay]

I’m trying to run default code after adding WPF window in VisualStudio 2019

Microsoft Visual Studio Community 2019
Version 16.4.2
script:

try
{
    Add-Type -AssemblyName PresentationCore,PresentationFramework,WindowsBase,system.windows.forms
} 
catch 
{
    Throw "Failed to load Windows Presentation Framework assemblies."
}

function Load-Xaml {
[xml]$xaml = Get-Content -Path $PSScriptRoot\WpfWindow1.xaml
$manager = New-Object System.Xml.XmlNamespaceManager -ArgumentList $xaml.NameTable
$manager.AddNamespace(“x”, “http://schemas.microsoft.com/winfx/2006/xaml”);
$xamlReader = New-Object System.Xml.XmlNodeReader $xaml
[Windows.Markup.XamlReader]::Load($xamlReader)
}

$window = Load-Xaml
$window.ShowDialog()

Error occurs while executes this line:
[Windows.Markup.XamlReader]::Load($xamlReader)

sorry it is in russian lang …

[ERROR] Исключение при вызове “Load” с “1” аргументами: “Вызов конструктора для типа “System.Windows.
[ERROR] Window”, удовлетворяющего указанным ограничениям привязки, привел к выдаче исключения.”
[ERROR] C:\Users\superuser\source\repos\PowerShellProject1\PowerShellProject1\WpfWindow1.xaml.ps1:15
[ERROR] знак:2
[ERROR] + [Windows.Markup.XamlReader]::Load($xamlReader)
[ERROR] + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[ERROR] + CategoryInfo : NotSpecified: ( [], MethodInvocationException
[ERROR] + FullyQualifiedErrorId : XamlParseException
[ERROR]
[ERROR] Невозможно вызвать метод для выражения со значением NULL.
[ERROR] C:\Users\superuser\source\repos\PowerShellProject1\PowerShellProject1\WpfWindow1.xaml.ps1:19
[ERROR] знак:1
[ERROR] + $window.ShowDialog()
[ERROR] + ~~~~~~~~~~~~~~~~~~~~
[ERROR] + CategoryInfo : InvalidOperation: ( [], RuntimeException
[ERROR] + FullyQualifiedErrorId : InvokeMethodOnNull
[ERROR]

this script runs exelent in PS ISE …

[kuznetcovay]

more info about error

Error occurs during this line of code only in Visual Studio 2019. VS Code an powershell ISE runs it successfully.
this line of code:

$err.CategoryInfo
Category : NotSpecified
Activity :
Reason : MethodInvocationException
TargetName :
TargetType :

$err.FullyQualifiedErrorId
XamlParseException

$err.InvocationInfo

MyCommand :
BoundParameters : {}
UnboundArguments : {}
ScriptLineNumber : 6
OffsetInLine : 2
HistoryId : -1
ScriptName : C:\Users\anton\source\repos\TestPS\WpfWindow1.xaml.ps1
Line : Windows.Markup.XamlReader::Load($xamlReader)

PositionMessage : C:\Users\anton\source\repos\TestPS\WpfWindow1.xaml.ps1:6 знак:2
+ Windows.Markup.XamlReader::Load($xamlReader)
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PSScriptRoot : C:\Users\anton\source\repos\TestPS
PSCommandPath : C:\Users\anton\source\repos\TestPS\WpfWindow1.xaml.ps1
InvocationName :
PipelineLength : 0
PipelinePosition : 0
ExpectingInput : False
CommandOrigin : Internal
DisplayScriptPosition :

$err.Exception
Исключение при вызове “Load” с “1” аргументами: “Вызов конструктора для типа “System.Windows.Window”, удовлетворяющего указанным ограничениям привязки, привел к выдаче исключения.”
translate by google:
Exception when calling “Load” with" 1 “arguments:” calling the constructor for type " System.Windows.Window " that satisfies the specified binding constraints resulted in an exception."

xaml (default after add wpf window in project):

<Window

xmlns=…

xmlns:x=…

Title=“MainWindow” Height=“350” Width=“525”>

<Grid>

    <Label Content="Label" HorizontalAlignment="Left" Margin="68,38,0,0" VerticalAlignment="Top" Width="197"/>

    <Button Content="Button" HorizontalAlignment="Left" Margin="307,41,0,0" VerticalAlignment="Top" Width="75"/>

</Grid>

[kuznetcovay]

I ve found the answer on this issue
In settings PoshTools it must be set “Single Threaded Apartment State”

[adam]

Ah, good catch. I’ll add that to the documentation and put a better error message in.

[Egatimra]

i think i was getting this same error and have ticked the “single Threaded Apartment state”

but now i get
The program ‘WpfWindow1.xaml.ps1: PowerShell Script’ has exited with code 0 (0x0).

but nothing appears?

this applies even when i dont actually make any change and it just loads th edefault wpf

any suggestions?

[adam]

Does this do the same thing when running the script from PowerShell.exe?

[Egatimra]

apologies i meant to mention that

No it runs from ise

[kuznetcovay]

1 Try set STA
2 when change powershell host ( for example from x64 to 32 bit version)
3 close VS
4 restart VS
5 wait PS host to completly load
6 check sta is On
7 try run your scrips …

[Egatimra]

Sorry Kuznetcovey

But im not sure what you mean or where i would do this?

[Egatimra]

full error:

[ERROR] Unable to find type [Windows.Markup.XamlReader].
[ERROR] At E:\VisualStudio\New folder\PowerShellProject1\WpfWindow1.xaml.ps1:6 char:2
[ERROR] + [Windows.Markup.XamlReader]::Load($xamlReader)
[ERROR] + ~~~~~~~~~~~~~~~~~~~~~~~~~~~
[ERROR] + CategoryInfo : InvalidOperation: (Windows.Markup.XamlReader:Typ
[ERROR] eName) [], RuntimeException
[ERROR] + FullyQualifiedErrorId : TypeNotFound
[ERROR]
[ERROR] You cannot call a method on a null-valued expression.
[ERROR] At E:\VisualStudio\New folder\PowerShellProject1\WpfWindow1.xaml.ps1:10 char:1
[ERROR] + $window.ShowDialog()
[ERROR] + ~~~~~~~~~~~~~~~~~~~~
[ERROR] + CategoryInfo : InvalidOperation: ( [], RuntimeException
[ERROR] + FullyQualifiedErrorId : InvokeMethodOnNull
[ERROR]
The program ‘WpfWindow1.xaml.ps1: PowerShell Script’ has exited with code 0 (0x0).

Opens fine in ISE

[adam]

What if you change this line:

[Windows.Markup.XamlReader]::Load($xamlReader)

To

[SYstem.Windows.Markup.XamlReader]::Load($xamlReader)

Can you also try putting this at the top of your script?

[System.Reflection.Assembly]::LoadWithPartialName('PresentationFramework') | Out-Null

It looks like it’s not loading WPF for some reason.

[Egatimra]

OK tried a couple of things.

1. created new solution, as is, tried to run got error.
   Made change to [Windows.Markup.XamlReader]::Load($xamlReader) and it run.
   Changed back to how it was…still run

2. created new solution run as is and worked.
   exited vs, restarted, created new solution, didnt work.
   Add line [System.Reflection.Assembly]::LoadWithPartialName(‘PresentationFramework’) | Out-Null
   while leaving other line as default…worked

[Egatimra]

and tried another test by opening one id created and started work on wheni discovered problem.

Made both changes and neither work.

get the “The program ‘WpfWindow1.xaml.ps1: PowerShell Script’ has exited with code 0 (0x0).”

message

[Egatimra]

seem this line is the key

[System.Reflection.Assembly]::LoadWithPartialName(‘PresentationFramework’) | Out-Null

[Shawn]

I experienced this same issue when going through the tutorial here:

https://docs.poshtools.com/powershell-pro-tools-documentation/visual-studio/user-interface-design/building-a-gui-with-windows-forms-in-visual-studio

You may want to update that, because it may cause frustration for people that are testing the software like I was.

Thanks for this thread, it did help solve the issue for me.