VB to C # translation

Application("myapp")= Server.CreateObject("APP.Engine ")

aa = Application("myapp").myMethod(2)

Application["myapp"]= Server.CreateObject("APP.Engine")

Application[" myapp"].myMethod(2)

'object' does not contain a definition for'myMethod'

((APP.Engine)Application["myapp"]).myMethod(2);

dymamic myApp = Application["myapp"];
myApp.myMethod(2);

In VB(ASP.NET)

Application("myapp")= Server.CreateObject("APP.Engine")

aa = Application("myapp").myMethod(2)

works.

I tried it in C#

Application["myapp"]= Server.CreateObject("APP.Engine")
 pre> 
But
 
 
Application["myapp"].myMethod(2)
Failed

'object' does not contain a definition for'myMethod'
How to expose public interface in C#? 

If you have access to the defined type (that is, not the original COM object), you can simply convert: 
 
((APP.Engine)Application["myapp"]).myMethod(2);
If you are using c#4.0, you can do the following:

dymamic myApp = Application["myapp"];
myApp.myMethod(2);
Otherwise, you will have to use reflection and Type.InvokeMember (...)Use dynamic method call