How do I add one attached property?

[tellblom]

Hi all
In the middle of a C# windows form project and need to add DataGridExtensions ( GitHub - dotnet/DataGridExtensions: Modular extensions for the WPF DataGrid control ) to my datagrid.
I have installed the extension.
To enable filtering in the DataGrid you should only, and I quote:

Filtering is enabled by simply adding one attached property to your DataGrid:

<DataGrid ItemsSource="{Binding Items}"
dgxataGridFilter.IsAutoFilterEnabled="True"/>

How and where do I add this?

I have tried to google this and I get Use BDC Explorer (that should be under View-Other Windows, but it's not)
I also found "How to register an attached property (WPF .NET)" in MS Docs but that shows a different way to to maybe the same thing.

So anyone can help me where I should put the above code?

 

[jmcilhinney]

You say that you're creating a Windows Forms project, in which case extensions for the WPF DataGrid are of no use to you.