I see that the usual TypeConverter code checks for type based on Type.FullName string. This made me wondering whether this is the fastest way to do it. It turns out, based on a simple test, that it could be roughly 19 times faster if compared against actual types instead. Below is my test case. On my computer first method ends after 574ms while the improved one takes 34ms (1m iterations).

private static bool Compare(Type destinationType)
        {
            switch (destinationType.FullName)
            {
                case "System.Int64":
                case "System.Int32":
                    return true;
                default:
                    return false;
            }
        }

        private static bool Compare2(Type type)
        {
            return type == typeof(long) || type == typeof(int);

        }

what typeconverter/code are you referring at exactly?

Otis wrote:

what typeconverter/code are you referring at exactly?

Well, for one the one from documentation: https://www.llblgen.com/documentation/4.2/SDK/gui_implementingtypeconverter.htm

But I think others out of the box use the same approach (comparing FullName).

Yeah I can create a static hashset of types in a static ctor, as they're always the same regardless and check the type with that. Will do that.

The one in the runtime contains typecode checks, which is faster than string comparisons. So the current code is optimal enough. The documentation has to be updated with that though.