C# conditional reference in solution-CodePudding

I am developing a C# application which uses a .tlb file as reference in its solution, which should be installed by another application - however I've recently discovered such use cases, where this other application would not be installed. In these cases my program fails to run correctly, my installer (made with

I suspect the behavior above is due to an initializer subclass which is called by the installer. I want this initializer class only call the discussed .tlb as reference, if it is actually useable/installed - so in case it's actually there, since it is only related to that other application which would install it to the user computer. How can I achieve this "conditional referencing" in my initializer.cs?

The exact code part:

using NGOptMan // This should be conditional or the line actually using it;
...
var optMan = (IOptionsManager)Activator.
 CreateInstance(Type.GetTypeFromProgID("SIDEXISNG.OptionsManager")); 
 // This is the only command where I would use this .tlb.

CodePudding user response：

You can make use of dynamic which allows you to utilise COM objects but without a type library.

Change:

var optMan = (IOptionsManager)Activator.CreateInstance(...)

dynamic foo = Activator.
 CreateInstance(Type.GetTypeFromProgID("SIDEXISNG.OptionsManager")); 

if (foo == null)
    return;  // failed

// Success
var optMan = (IOptionsManager)foo;  // Now cast using the typelib

NOTE the use of dynamic and the removal of the cast.