Through the Interface

Exposing AutoCAD's Properties Palette functionality to .NET - Part 1

A huge thanks to Cyrille Fauvel, who manages DevTech's Media & Entertainment team but still finds the time to dip into the odd deeply-technical, AutoCAD-related issue. Cyrille provided the original article on this topic late last year, but it's taken me time to get around to editing and publishing it. A quick tip... if you're not interested in the technical details of how Cyrille has exposed the various Properties Palette interfaces to .NET, you can safely skip this post and join us again when we go ahead and make use of the implementation to add dynamic properties to core... Read more →

Adding custom properties to AutoCAD's rollover tooltip and its quick properties panel

This topic is a little on the advanced side - it requires the use of C++ and some knowledge of COM - but I felt it was worth covering, as you can get some interesting results without a huge amount of effort. Since we introduced the Properties Palette (once known as the Object Property Manager (OPM) and otherwise referred to as the Properties Window) back in AutoCAD 2004 (I think it was) it has become a core tool for viewing and editing properties of AutoCAD objects. In AutoCAD 2009 we have taken the concept further, allowing properties to be... Read more →

Changing the colour of the contents of an AutoCAD block using .NET

Here's a question that came in to us, recently: How can I show the AutoCAD color dialog from .NET? I need to allow the user to select a block, show the AutoCAD color dialog and apply the selected color to the contents of the selected block. A new member of DevTech Americas - Augusto Gonçalves, who's based in our São Paulo office - answered with the following code (which I've modified slightly, mostly to follow this blog's coding conventions). Thanks, Augusto! By the way, these previous posts may also be useful to those interested in this topic. Here's the... Read more →

Creating a layer group inside AutoCAD using .NET

The following question came in as a comment on this previous post: Your example above shows how to create a property type filter, how do you add layers to a group type filter (LayerGroup class)? I can create the group filter but can't figure out how to add layers to the group. The filterexpression method is available but doesn't seem to work (at least not like with the LayerFilter object) To tackle this, let's start by looking at the documentation on the LayerGroup class in the .NET Reference (currently part of the ObjectARX Reference): LayerGroup is derived from LayerFilter... Read more →

Adding and removing AutoCAD layer filters using .NET

This question came in by email last week: The last two days I am struggling with adding a new LayerGroup to HostApplicationServices.WorkingDatabase.LayerFilters.Root. I simply cannot get it working. Is it possible to write a blog item with example on this? An interesting question and it can indeed be quite tricky to understand how this works. For those of you who are ADN members, here's a DevNote covering the basics, which I've taken and extended for this post. When working with LayerFilters, it's important to know that the Database property providing access to the list of current LayerFilters does so... Read more →

Extracting XML data from drawings using a new .NET API in AutoCAD 2009

This post is the latest in the series of closer looks at the new APIs in AutoCAD 2009. It covers the Data Extraction API, a new .NET API allowing you to drive the Data Extraction feature inside AutoCAD. There is a very thorough C# sample included on the ObjectARX SDK (under samples/dotNet/DataExtraction), so I thought I'd focus on a much simpler example where we extract data from a single drawing. Here's the C# code: using System.Collections.Generic; using Autodesk.AutoCAD.ApplicationServices; using Autodesk.AutoCAD.EditorInput; using Autodesk.AutoCAD.Runtime; using Autodesk.AutoCAD.DataExtraction; namespace DataExtraction { public class Commands { const string path = @"c:\Program Files\Autodesk\AutoCAD 2009\Sample\"; const... Read more →

Modifying the color, linetype and lineweight of an AutoCAD entity using standard dialogs from .NET

In the last post we saw code to display and use AutoCAD's built-in colour, linetype and lineweight dialogs. In this post we extend that by using each of them in sequence to display various properties of an entity, allowing the user to modify them. While this is slightly more "real world" than the last post, it doesn't really make sense to implement a command such as the one below (the property palette is much better, for instance :-). The main purpose is to show how to set the initial values in the various dialogs and afterwards to make use... Read more →

Using standard AutoCAD dialogs to select colors, linetypes and lineweights with .NET

AutoCAD has a number of handy dialogs available in the "Autodesk.AutoCAD.Windows" namespace. The following code shows how to use three, in particular: ColorDialog, LinetypeDialog and LineWeightDialog. These three classes allow you to very easily implement user-interfaces selecting their corresponding properties. Here's the C# code: using Autodesk.AutoCAD.Runtime; using Autodesk.AutoCAD.ApplicationServices; using Autodesk.AutoCAD.DatabaseServices; using Autodesk.AutoCAD.EditorInput; using Autodesk.AutoCAD.Windows; namespace AutoCADDialogs { public class Commands { [CommandMethod("CDL")] public void ShowColorDialog() { Document doc = Application.DocumentManager.MdiActiveDocument; Database db = doc.Database; Editor ed = doc.Editor; ColorDialog cd = new ColorDialog(); System.Windows.Forms.DialogResult dr = cd.ShowDialog(); if (dr == System.Windows.Forms.DialogResult.OK) { ed.WriteMessage( "\nColor selected: " + cd.Color.ToString() );... Read more →

Understanding the properties of textual linetype segments in AutoCAD

In the last post we looked at using .NET to define complex linetypes containing text segments. In the post I admitted to not knowing specifics about the properties used to create the text segment in the linetype, and, in the meantime, an old friend took pity on me and came to the rescue. :-) Mike Kehoe, who I've known for many years since we worked together in the Guildford office of Autodesk UK, sent me some information that I've reproduced below. Mike now works for Micro Concepts Ltd., an Autodesk reseller, developer and training centre. He originally wrote the... Read more →

Creating a complex AutoCAD linetype containing text using .NET

In my last post we saw some code to create a simple linetype using .NET. As a comment on that post, Mark said: Kean, i tried you code and it works great and it also got me thinking... is it possible to programmitically add text in as well? I've tried using ltr.SetTextAt(1, "TEST") but so far i've had no luck, any suggestions??? It turned out to be quite a bit more complicated to make a linetype containing text than merely calling SetTextAt() on one of the segments. In order to understand what properties needed setting, I first loaded the... Read more →

Creating an AutoCAD linetype programmatically using .NET

Happy New Year, everyone! I had a very relaxing break over the holiday period: during the better part of two weeks I managed to stay away from my PC and even my BlackBerry, which I admit I'm generally not very good at ignoring. So now I'm easing back into the swing of things, remembering how to type and open modelspaces, among other things. :-) To save my brain from unnecessary stress during the first few weeks of 2008, I've decided to take inspiration from the ADN website. Today's post is based on this DevNote, which shows how to create... Read more →

Using a palette from .NET to display properties of multiple AutoCAD objects

After a brief interlude we're back on the series of posts showing how to implement basic user-interfaces inside AutoCAD using .NET. Here's the series so far: Using a modal .NET dialog to display AutoCAD object properties Using a modeless .NET dialog to display AutoCAD object properties Using a modeless .NET dialog to display properties of multiple AutoCAD objects In this post we're going to swap out the modeless form we've been using in the last few posts in the series and replace it with an instance of AutoCAD's in-built palette class (Autodesk.AutoCAD.Windows.PaletteSet). Firstly, why bother? Well, the PaletteSet class... Read more →

Using a modeless .NET dialog to display properties of multiple AutoCAD objects

After a few comments on this previous post I decided that, rather than rushing on to show palettes, I'd first extend the existing code to work with multiple entities and provide specific support for solids. Here are the main changes to the way the code works: Changes to the Commands class The form object is now a static member, and so is shared across documents To support this I added a DocumentCreated event to make sure it gets added when new documents are created or opened Initialization/termination happens via IExtensionApplication, not on class construction/destruction In OnMonitorPoint we get the... Read more →

Using a modeless .NET dialog to display AutoCAD object properties

In this previous post we looked at creating a simple modal dialog and using it to display object properties. This post looks at the structural changes you need to make to your application for the same dialog to be used modelessly. In a later post we'll look at the benefits you get from leveraging the Palette system for modeless interaction inside AutoCAD. Firstly, let's think about the interaction paradigm needed by a modeless dialog. A few things come to mind: There is no longer a need to hide and show the dialog around selection Rather than asking the user... Read more →

Using a modal .NET dialog to display AutoCAD object properties

Firstly, a big thanks for all your comments on the first anniversary post. It's good to know that people are finding this blog useful, and I hope the flow of ideas (internal and external) doesn't dry up anytime soon. So keep the comments coming! :-) This post is going to start a sequence of posts that look at how to integrate forms into AutoCAD. This post looks at modal forms, and later on we'll look more at modeless forms and - in particular - palettes. Just to be clear, these posts will focus on the basic integration - the... Read more →

Getting the type of an AutoCAD solid using .NET

Now this may seem like a very trivial post, but this was actually a significant problem for my team when preparing the material for the Autodesk Component Technologies presentation we delivered at last year's DevDays tour. Basically the "type" (or really "sub-type") of a Solid3d (an AcDb3DSolid in ObjectARX) is not exposed through ObjectARX and therefore neither is it exposed through the managed interface. It is possible to get at the information from C++ using the Brep API, but this is currently not available from .NET (and yes, we are aware that many of you would like to see... Read more →

Using the COM interface for AutoCAD objects from .NET

This question came in a couple of weeks ago from csharpbird, and I promised myself to turn it into a post: The Hatch class of the current AutoCAD version does not provide the OriginPoint property.How to get/set the OriginPoint of the Hatch object using P/Invoke? The reason I wanted to delay making an official post is that I have good news (that I couldn't talk about until the product was announced): the Autodesk.AutoCAD.DatabaseServices.Hatch object now has an Origin property in AutoCAD 2008. :-) But this does raise an interesting topic - how to get at information that isn't available... Read more →

Using .NET reflection with AutoCAD to change object properties - Part 2

In the last post we looked at some code that combined user-input from the AutoCAD command-line with .NET reflection to determine an object type, a property belonging to that type, and the value to which we want to change that property on instances of that type (phew!). Here's where we look at hooking that up with some code to work recursively through the drawing database and make the changes to the actual objects. Firstly, let's look at some C# code to check the type of an entity, and then - as appropriate - to query the property's value and... Read more →

Using .NET reflection with AutoCAD to change object properties - Part 1

I ended up having a fun weekend, in spite of the circumstances. My wife and eldest son were both sick with a cold (which, inevitably enough, I now feel I’m coming down with myself), so we mostly stayed around at home. So I got to spend a little time working on an idea that came to me after my last post. While the code I provided last time does pretty much exactly what was asked of it (allowing the person who requested it to change the colour of every entity in the modelspace – whether in nested blocks or... Read more →

Changing the colour of nested AutoCAD entities through .NET

Someone asked me earlier today how to iteratively change the color of entities inside blocks. The following code uses a recursive helper function to iterate down through the contents of a block, changing the various entities (other than block references, for which we simply recurse) to a specified colour. Here's the C# code: using Autodesk.AutoCAD.ApplicationServices; using Autodesk.AutoCAD.DatabaseServices; using Autodesk.AutoCAD.EditorInput; using Autodesk.AutoCAD.Runtime; using Autodesk.AutoCAD.Colors; namespace BlockTest { public class BlockCmds { [CommandMethod("CC")] public void ChangeColor() { Document doc = Application.DocumentManager.MdiActiveDocument; Database db = doc.Database; Editor ed = doc.Editor; PromptIntegerResult pr = ed.GetInteger( "\nEnter color index to change all entities to:... Read more →