Interop Activex or .NET API? Which one is recommended?

[apoorva_jukanti]

Hi,

My requirement is migrating a desktop application from .vbp to .net. 

Present code in vb is using ActiveX object to launch the autocad application and insert blocks and deal with the block attributes. The major existing project is to use the existing drawing blocks in specific path and modify and replace them.

Now while migrating it to .net which is the optimized way(recommended waY) to implement the above mentioned functionality, ActiveX or Autocad .Net API?

Please suggest a viable solution.

[_gile · Accepted solution]

Hi,

The .NET API is more powerfull but it cannot be directly used as stand-alone executable (exe). See this topic.

[apoorva_jukanti]

Can you please provide examples of using ActiveX Interop  in C# other than launching autocad application ?  For Example: InsertBlock Method(ActiveX) 

[apoorva_jukanti]

Is there any possibility of Deprecating ActiveX in future?

As Microsoft might stop supporting VB in future?

[_gile]

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@apoorva_jukanti  a écrit :

Can you please provide examples of using ActiveX Interop  in C# other than launching autocad application ?  For Example: InsertBlock Method(ActiveX) 

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If you absolutely want to use ActiveX Interop in a .NET plugin (which most AutoCAD .NET developers deprecate), you can simply get the the AcadApplication object from the Application.AcadApplication property.

var acadApp = (AcadApplication)Application.AcadApplication;
var thisDrawing = acadApp.ActiveDocument;
var blockRef = thisDrawing.ModelSpace.InsertBlock(Point3d.Origin.ToArray(), blockName, 1.0, 1.0, 1.0, 0.0);

[apoorva_jukanti]

No, I would like to use .Net API.

But, My requirement is launching autocad from .net (which can be done only using ActiveX) and then use the existing .dwg from a folder and modify them.

Can I use ActiveX object for launching Autocad and then use .Net api for modifying the drawing ?

[_gile]

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@apoorva_jukanti  a écrit :

No, I would like to use .Net API.

But, My requirement is launching autocad from .net (which can be done only using ActiveX) and then use the existing .dwg from a folder and modify them.

Can I use ActiveX object for launching Autocad and then use .Net api for modifying the drawing ?

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You can use the same "ConnectToAcad" method of the example in this topic from a stand-alone executable (without the CommandMethodAttribute).

[apoorva_jukanti]

Can you please tell the valid nuget for using Interop.AutoCAD.dll

[_gile]

https://www.nuget.org/packages/AutoCAD.NET.Interop

[apoorva_jukanti]

if I install the latest autocad 2025 nuget, i will be able to use lower versions of autocad also right?

[apoorva_jukanti]

it shows it does not support 

[_gile]

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@apoorva_jukanti  a écrit :

if I install the latest autocad 2025 nuget, i will be able to use lower versions of autocad also right?

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No. You have to install the package corresponding to the targeted AutoCAD version.

[kerry_w_brown · Accepted solution]

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@apoorva_jukanti wrote:

it shows it does not support 

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//

the wording is "provide support"

That means that nuget won't answer questions about the files provided . . . which I think is typical, they just push the files provided by their clients.
sort of like : don't complain to the postman about the bills you get in the mail.

[apoorva_jukanti]

Is there a way, I can support all versions of autocad? using the AutoCAD.NET.Interop NuGet in my c# code

[apoorva_jukanti]

Can you please provide nuget that supports .net framework4.8 and autocad 2025

[_gile]

As said upper the COM API is not version compatible.

You have to build separated assembies for each targeted AutoCAD version (at least major version) referencing the corresponding libraries.

.

[norman.yuan]

@apoorva_jukanti 

Judging by the questions you asked here and in the other forum (ObjectARX), it seems to me that you are probably not very familiar with AutoCAD programming and the various types of AutoCAD APIs that could be used in different scenarios/application types.

You might as well provide some detailed description of what type of application you want to develop, some business requirements/workflows...because these things decide if your goal is doable, and if yes, what AutoCAD API should be used. At least people do not have to keep guessing an answer you really want to hear.

[daniel_cadext]

Yes, you can use late binding and dynamic coding styles, this will eliminate the need for hard references.

[JPR_INTT]

Hey everyone, this is the closest topic I've founded related to my situation. I'm creating a revit plugin, but I'd like it to retrieve some geometry from AutoCAD, so is it possible doing with .NET or only ActiveX?
Actually, I have a button on the revit form, when I click the button, I need to select a polyline in AutoCAD to get the points.

[norman.yuan]

When you say "...need to select a polyline in AutoCAD to get the points...", by "select", do you mean the user HAS TO manually/interactively select an Acad entity in AutoCAD's editor (i.e. running AutoCAD session's drawing editing window)? If so, since the selecting process is initiated from within Revit, yes, you have to use AutoCAD COM/ActiveX API to do it.

In general, this would be an quite awkward operation, because the user has to switch attention between 2 heavy desktop apps. IMO, I would try to avoid it as much as possible.

If the target entity or entities in a drawing file can somehow be identified by code (say, by creating the drawing contents following a set of well-defined CAD standards), then this "going-to-another-running-app-for-selecting" thing would be avoided, and you could be spared from relying on running 2 heavy desktop apps side by side and switching user's attention back and forth.