Method not found 'System.String System.AppDomainSetup.get_ApplicationName().'

[Stacy O]

Hello,

I created a new WPF .NET Application targeting .NET 9.0 using. Using Syncfusion version 31.2.2, I added a TabControlEx to the MainWindow as follows:

<Window x:Class="Syncfusion_WpfApp2.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:Syncfusion_WpfApp2"

        xmlns:syncfusion="http://schemas.syncfusion.com/wpf"

        mc:Ignorable="d"

        Title="MainWindow" Height="450" Width="800">

    <Grid>

        <syncfusion:TabControlExt Name="tabControlExt">

            <syncfusion:TabItemExt Header="tabItem1">

                <TextBlock Name="textBlock" Text="This is the first tab item." />

            </syncfusion:TabItemExt>

            <syncfusion:TabItemExt Header="tabItem2">

                <TextBlock Name="textBlock1" Text="This is the second tab item." />

            </syncfusion:TabItemExt>

            <syncfusion:TabItemExt Header="tabItem3">

                <TextBlock Name="textBlock2" Text="This is the third tab item." />

            </syncfusion:TabItemExt>

        </syncfusion:TabControlExt>

    </Grid>

</Window>

The application builds, but throws the following error at runtime:

System.Windows.Markup.XamlParseException

  HResult=0x80131501

  Message='The invocation of the constructor on type 'Syncfusion.Windows.Tools.Controls.TabControlExt' that matches the specified binding constraints threw an exception.' Line number '11' and line position '10'.

  Source=<Cannot evaluate the exception source>

  StackTrace:

<Cannot evaluate the exception stack trace>

  This exception was originally thrown at this call stack:

Inner Exception 1:

MissingMethodException: Method not found: 'System.String System.AppDomainSetup.get_ApplicationName()'.

Line 11 in the code is: <syncfusion:TabControlExt Name="tabControlExt">

I have been able to use other Syncfusion controls (sfDataGrid and Ribbon) in the same application setup without any issues.

What do I need to do in order to use the TabControlEx in my project?

Thank you!

[Victoria Farrell]

That error usually means your .NET runtime version doesn’t include the AppDomainSetup.ApplicationName API anymore. It’s been removed in newer .NET versions dude theft auto.

Try:

• Targeting an earlier .NET version (like 8.0).

• Cleaning bin/obj and updating to the latest Syncfusion build that supports .NET 9.

It’s a compatibility issue between your .NET version and the library.

[Karthick Arjunan]

Hi Stacy O,

We have created a simple sample based on the information you provided, and in which the TabControlExt rendered properly without any issues. We were unable to reproduce the reported exception in the sample. For your reference, we have attached the sample project and a demo video.

If we have misunderstood your query, could you please share the following details,

• Are you using any theme in your application?
• Please provide more details about your requirement along with a screenshot or video of the issue.
• If possible, share a modified sample that replicates the issue.

This will help us provide a solution as quickly as possible.

Regards,
Karthick Arjunan

Attachment: SampleAndDemoVideo_9b422df3.zip