Registering SOLIDWORKS add-in using xCAD

xCAD framework will automatically register the add-in by performing 2 steps (no need to run custom regasm commands, no need to call any static classes):

• Registering the assembly as COM via regasm for .NET Framework add-ins and regsvr32 for .NET Core add-ins. It is however possible to disable this behavior by adding the XCadRegDll property into the .csproj PropertyGroup. In this case you can manually register the add-in via command line or post build actions.

<PropertyGroup>
    <XCadRegDll>false</XCadRegDll>
</PropertyGroup>

• Adding the required parameters to the Windows Registry. To skip an automatic registration decorate the add-in class with Xarial.XCad.Extensions.Attributes.SkipRegistrationAttribute.

[ComVisible(true)]
[Extensions.Attributes.SkipRegistration]
public class SampleAddIn : SwAddInEx
{

It might be required to run Visual Studio As Administrator to allow the registration of COM object and adding the keys to registry.

.NET Framework

To define add-in just add the ComVisibleAttribute.

Although it is not a essential requirement, it is recommended to assign the GUID to the add-in class via GuidAttribute.

[ComVisible(true)]
public class SampleAddIn : SwAddInEx
{
    public override void OnConnect()
    {
    }
}

.NET Core

Unlike .NET Framework registration, COM class must be decorated with GuidAttribute.

In addition, it is required to add the EnableComHosting property into the *.csproj file and explicitly call the registration due to known limitation of .NET Core as shown below:

<PropertyGroup>
    <EnableComHosting>true</EnableComHosting>
</PropertyGroup>

[ComVisible(true), Guid("612378E1-C962-468C-9810-AF5AE1245EB7")]
public class SampleAddIn : SwAddInEx
{
    [ComRegisterFunction]
    public new static void RegisterFunction(Type t)
    {
        SwAddInEx.RegisterFunction(t);
    }

    [ComUnregisterFunction]
    public new static void UnregisterFunction(Type t)
    {
        SwAddInEx.UnregisterFunction(t);
    }

    public override void OnConnect()
    {
    }
}

It is also required to change the SDK of the add-in project to Microsoft.NET.Sdk.WindowsDesktop and set the UseWindowsForms attribute. This would enable the support for resources and other windows specific .NET classes used by framework.

<Project Sdk="Microsoft.NET.Sdk.WindowsDesktop">

  <PropertyGroup>
    <UseWindowsForms>true</UseWindowsForms>
  </PropertyGroup>

Note, .NET Core is a new framework and there were some compatibility issues and conflicts reported with other 3rd party libraries when running as in-process application (i.e. add-in). It is recommended to use .NET Framework for add-ins development where possible until .NET Core is fully supported by SOLIDWORKS host application.

Refer Accessing SQL database via Entity Framework example for the demonstration of the SOLIDWORKS add-in in .NET Core.

Unregistering add-in

Add-in will be automatically removed and all COM objects unregistered when project is cleaned in Visual Studio