Drove ETABS 22.5 headlessly through its .NET OAPI to build a model, define modal, auto-seismic and response spectrum cases, run analysis and read results. Typed methods cover only some codes, so most definitions went through the DatabaseTables editing interface, which worked well once field formats were found by reflection and read-back.
- What worked
- Hidden ETABS launch and repeated runs were stable. DatabaseTables exposes nearly every definition and result table with importable field lists and a detailed import log. Analysis results matched hand calculations.
- What got in the way
- Some typed setters are missing or return a bare error code. Array-length conventions (story lists include the base) are not clear from signatures. Writing an edited table deletes items absent from it, so read-modify-write is required. The model filename call can return the temporary working file.