c# - How to cast Object to its actual type?

Question

If I have:

void MyMethod(Object obj) {   ...   }

How can I cast obj to what its actual type is?

Answer 1

If you know the actual type, then just:

SomeType typed = (SomeType)obj;
typed.MyFunction();

If you don't know the actual type, then: not really, no. You would have to instead use one of:

• reflection
• implementing a well-known interface
• dynamic

For example:

// reflection
obj.GetType().GetMethod("MyFunction").Invoke(obj, null);

// interface
IFoo foo = (IFoo)obj; // where SomeType : IFoo and IFoo declares MyFunction
foo.MyFunction();

// dynamic
dynamic d = obj;
d.MyFunction();