How to develop and run .NET plugins in BricsCAD V26?

Starting with BricsCAD® V26, the managed runtime has been upgraded to .NET 8 (formerly .NET Core).

This replaces the legacy .NET Framework 4.8 runtime used in previous versions.

Note: Support for the legacy .NET Framework 4.8 and older is deprecated in BricsCAD® V26.

End-User Requirements

To load and run .NET-based plugins in BricsCAD® V26:

Install .NET 8 Desktop Runtime (x64).
You can download it from here.
Ensure the installed runtime architecture matches the BricsCAD® installation (x64).
If a plugin fails to load with the following error, it means the file was blocked by Windows security:
```
Could not load file or assembly 'file:///<path-to-file> or one of its dependencies. 
Operation is not supported. (Exception from HRESULT: 0x80131515)
```
To fix it, right-click the plugin DLL, go to Properties and choose Unblock.

Plugins built for .NET Framework 4.8 must be rebuilt using the .NET 8 SDK before they can be loaded in BricsCAD® V26.

Use the SDK-style project format introduced with .NET Core.

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net8.0-windows</TargetFramework>
  </PropertyGroup>
</Project>

Plugin migration instructions can be found in the README.txt file in the API samples folder of the BricsCAD® install directory.

The default path of the README.txt file is:

C:\Program Files\Bricsys\BricsCAD V26 en_US\API\dotnet\README.txt