How does the .net program use the com interface inheritance relationship?

zzgh55555

How does the .net program use the com interface inheritance relationship?

For example, the Com class "ComClass" inherits the Com interface "ComInterface", but after .net references them, ComClass and ComInterface are irrelevant. If you write
ComInterface obj = new ComClass();
It is reported that it cannot be converted. May I ask ComClass to be converted to ComInterface?

zzgh55555

By the way, is it troublesome for .net to use com components? I think the c# language does not support com features such as optional parameters, default members, etc. I don't know if vb.net is better.

zzgh55555

By the way, for the optional parameters of the com method in c#, what to pass is equivalent to not passing it? What is the equivalent of "Missing" in com?

darknesslan

You can pass Type.Missing

zzgh55555

darknesslan
Type.Missing doesn't seem to work. For example, the optional parameter is of int type. Type.Missing obviously does not match the int type.

zzgh55555

Is there any expert who can help to solve it?

zzgh55555

Just found out that it’s okay to turn around, Khan!
ComInterface obj = (ComInterface)(new ComClass());

Thank you for your participation!