When you extend Esri's ArcMap with both an Extension, a Toolbar and a number of Commands, is the order in which these categories are loaded by ArcMap well-defined? (I.e. are Commands always loaded before Toolbars, Extension always loaded before Commands, etc.)

2 Answers 2


In ArcGIS Desktop 9.x, I'm pretty sure it is Extensions, Commands then Toolbars. I'd have to check with 10.0 since they are using a different method for loading custom code (although it's prob still the same)'


I'd recommend reading the "About extensions" topic in Extending ArcObjects | ESRI Developer Network (Wayback Machine link) which covers just-in-time extension loading. Ideally all extensions should be JIT extensions. Tools and commands can control the startup of a JIT extension etc.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.