Question

I see code similar to the following sprinkled about some native WPF controls:

static MyControl {
    Type typeFromHandle = typeof(MyControl);

    // Which is used in various places
    SomeProperty.OverrideMetadata(typeFromHandle, ...);
    CommandManager.RegisterClassInputBinding(typeFromHandle, ...);
    EventManager.RegisterClassHandler(typeFromHandle, ...);
}

Seems like the following code would have the same performance:

static MyControl {
    SomeProperty.OverrideMetadata(typeof(MyControl), ...);
    CommandManager.RegisterClassInputBinding(typeof(MyControl), ...);
    EventManager.RegisterClassHandler(typeof(MyControl), ...);
}

Does this approach offer any benefit performance wise when JIT-ing the code or during runtime?

Answer 1

Caching of typeof will give you a small performance boost. The following page gives the benchmarks:

Typeof expression used: 2.55 ns
Type object cached:     0.64 ns

If you typeof a lot, or care about nanoseconds, then this might matter to you!