CAD Software Guides

AutoCAD API Development for Engineering Automation

Engineering companies produce thousands of AutoCAD drawings a year. AutoCAD's APIs let them automate the repetitive parts and connect drawings to the rest of the business.

July 17, 20267 min readENGIMANDI CAD Team

The AutoCAD APIs

APILanguageStrength
AutoLISP / Visual LISPLISPQuick utilities, huge existing code base
.NET APIC#, VB.NETModern add-ins, UI, integration
ObjectARXC++Custom objects, performance
ActiveX / COMVBA, external appsDriving AutoCAD from other programs (legacy)
JavaScriptJSWeb-based palettes inside AutoCAD
APS Design AutomationAny (REST)Cloud processing of DWG files

Engineering automation use cases

  • Drawing generation: layouts, sections and details from parameters or data.
  • Title blocks and revisions: synchronised across whole drawing sets.
  • Schedules and BOMs: extracted from blocks and attributes to Excel or ERP.
  • Standards checking: layers, styles and naming against company rules.
  • Batch plotting and exports: PDF, DWF and DXF for entire projects.
  • Data links: equipment, cable or pipe data from databases.
  • Discipline tools: structural, piping, electrical and civil calculations turned into geometry.

Our project approach

  1. Workshop to understand the workflow and pain points.
  2. Specification with sample drawings and expected outputs.
  3. Prototype on real drawings; user feedback.
  4. Development with testing on multiple AutoCAD versions.
  5. Deployment, training and support.

Deployment with bundles

AutoCAD's autoloader loads plugins from .bundle folders described by a PackageContents.xml file. This makes installation, updates and support for several AutoCAD versions clean and simple.

%APPDATA%\Autodesk\ApplicationPlugins\EngiTools.bundle\
    PackageContents.xml
    Contents\Win64\EngiTools.dll
    Contents\Resources\EngiTools.cuix

Supporting new AutoCAD releases

AutoCAD releases a new version every year. Well-structured code, with version-specific parts isolated, keeps upgrades quick. Note that AutoCAD 2025 moved to .NET 8, so older .NET Framework add-ins need migrating.

Plan for version upgrades from day one. It keeps your tools running for years.

AutoCAD API development with ENGIMANDI

See AutoCAD API development and our earlier comparison of AutoLISP vs .NET vs ObjectARX.

EM
ENGIMANDI CAD Team

We build CAD add-ins, automation and integrations for engineering and manufacturing companies worldwide.