This call creates an instance at a specific given express ID, the instance is only created if the express ID was not used yet


public const string ifcenginedll = @"ifcengine.dll";

[DllImport(IFCEngineDLL, EntryPoint = "sdaiCreateInstanceEI")]
public static extern Int32 sdaiCreateInstanceEI(int_t model, int_t entity, Int64 expressID);    

Property model

Size: 32 bit / 4 byte (value)
The handle to the model. The model handle is static during its existance. Several models can be opened simultaniously within one session. Different models are always independent, threads are allowed to be running on different models simultaniously.

Property entity

Size: 32 bit / 4 byte (value)

Property expressID

Size: 64 bit / 8 byte (value)