Introduction to ActiveX/COM Plugins

There are two types of ActiveX/COM plugins:

Out-Process: The plugin runs as a separate .exe file.
In-Process: Load and run the pluglin using the NETLOAD command.

Out-Process Active/COM Plugins

Create a new C# or VB.NET project using the Visual Studio project Wizard( **minimum requirement .NET Framework v4.5.2).
One can either create Windows Form Application, Console Application, or Class Library.
From Solution Explorer, add references to OdaX_x.xx_xx*.dll and ARESC.exe from ARES Commander installation folder.
You can add references by searching PCAD_AC_X and PCAD_DB_X from COM Assemblies.
You can see the available NameSpaces, Class Methods, and Properties in each assembly using Object Browser.
Rename Program.cs to PluginCommands. This changes class Program to class PluginCommands as in the following example.
```
namespace SamplePlugins
{
	class PluginCommands
	{
		static void Main(string[] args)
		{
		}
	}
}
```
There are two ways to work with an out-process plugin:
- Create a new Instance
- Attach the debugger while the application is running

To create an Instance of AcadApplication, use PCAD_AC_X.
This call starts ARES Commander directly.

using PCAD_AC_X;

namespace SamplePlugins
{
	class PluginCommands
	{
		static void Main(string[] args)
		{
			Application app = new AcadApplication();
		}
	}
}

If ARES Commander is already running, use a version dependent ProgIDs or an independent one as in the following example.
For Marshal, use System.Runtime.InteropServices.

using PCAD_AC_X;
using System.Runtime.InteropServices;

namespace SamplePlugins
{
	class PluginCommands
	{
		static void Main(string[] args)
		{
			AcadApplication app = (PCAD_AC_X.AcadApplication)Marshal.GetActiveObject("PCAD_AC_X.AcadApplication");
		}
	}
}

Accessing Documents and Active Documents

From the application object you can access collection of documents or active documents and preferences.

The following code iterates through the document collection.

foreach(AcadDocument Doc in app.Application.Documents)
{
	Console.Writeline("\n" + Doc.Name);
}

The following code gets the active document.

AcadDocument NewDrawing;
NewDrawing = app.ActiveDocument;

The following code accesses the display preferences.

IAcadPreferencesDisplay AcadPref;
AcadPref = app.Preferences.Display;
int Size = AcadPref.CursorSize;

Prompting For User Input

Utility functions let you request input from the user and perform geometric calculations. You can access Utility functions through the ActiveDocument object. Various Utility functions prompt user for input. For example, GetInteger() allows integer input. Similar methods allow prompting for Angle, Distance, AngleFromAxis, and Keyword.

For reference, see the following code.

int promptInteger;
//With prompting to user
promptInteger = app.ActiveDocument.Utility.GetInteger("Enter an integer")

//Without prompting to user
promptInteger = app.ActiveDocument.Utility.GetInteger();

In-Process Active/COM Plugins

Create a new C# or VB.NET project using Visual Studio project Wizard( **minimum requirement .NET Framework v4.5)
From Solution Explorer, add references to OdaX_x.xx_xx*.dll, ARESC.exe, and TD_Mgd_x.xx_xx.dll from ARES Commander installation folder.
You can see the available NameSpaces, Class Methods, and Properties in each assembly using Object Browser.
Rename Program.cs to PluginCommands. This changes class Program to class PluginCommands as in the following example:
```
namespace ActiveXCOMSample
{
	public class PluginCommands
	{
	}
}
```
Defining a command uses Runtime namespace to access the CommandMethod attribute and adds a method with this attribute. See AnyFunctionName() in the following example.
The following example defines the MySampleCommand command.
```
using Teigha.Runtime;

namespace ActiveXCOMSample
{
	public class PluginCommands
	{
		[CommandMethod("MySampleCommand")]
		public void AnyFunctionName()
		{
		}
	}
}
```
Using a similar procedure, you can create all types of in-process plugins.
Building the sample project generates a dll file named <YourProjectName.dll>

Running the NETLOAD Command

Start ARES Commander.
Type NETLOAD at the command prompt and press Enter. Navigate to PluginCommands.dll and load it.
The command window displays a confirmation message.
Run MySampleCommand which executes the AnyFunctionName method.
Because ARES Commander is already running, use GetActiveObject method instead of creating an instance of AcadApplication.
For Marshal, use System.Runtime.InteropServices

Use the same steps to access various ActiveX/COM objects and collections.

using Teigha.Runtime;
using PCAD_AC_X;
using System.Runtime.InteropServices;

namespace ActiveXCOMSample
{
	public class PluginCommands
	{
		[CommandMethods("MySampleCommand")]
		public void AnyFunctionName()
		{
			IAcadApplication app = (IAcadApplication)Marshal.GetActiveObject("PCAD_AC_X.AcadApplication");
		}
	}
}

Migrating AutoCAD® ActiveX PlugIn Application to ARES Commander

You can easily migrate ActiveX/COM applications running on AutoCAD® platform to ARES Commander.

The following changes are necessary:

Replace AutoCAD® ActiveX/COM assemblies by ARES ActiveX/COM (OdaX_x.xx_xx and ARESC.exe) assemblies.
Replace Autodesk.AutoCAD namespace by Teigha namespace in source code.
Replace AutoCAD to PCAD_AC_X and AXDBLiB to PCAD_DB_X in source code.