Allow single parameter with any type when binding to method - #21867
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* Allow single parameter with any type when binding to method * Port method binding logic to ReflectionBinding * Don't depend on the order of methods * Handle overrides properly * Fix nullability warning
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What does the pull request do?
#21617 made the chosen overload consistent when binding a command property to a method, instead of it being undefined behavior: the parameter must be an
object.While doing so, it also broke code that strongly typed the parameter with a single overload, see #21833.
This PR improves the logic to allow a single overload with a single parameter to always match (the parameter's type doesn't matter in this case), which should cover the most common scenarios, as view models don't typically overload such methods.
New logic
object, it is chosen.Any other combination results in an error. For example multiple one-parameter overloads (without
object) don't work. There is no overload resolution matching C#: we don't want to implement such a complex algorithm, and the exact parameter type might not be known at compile time.These changes apply to both compiled and reflection bindings.
There is still one difference between the two binding types though: reflection bindings convert the parameter to the proper type at runtime, compiled bindings don't (the correct type must be passed, or an
InvalidCastExceptionis thrown). This is to avoid callingTryConvert, which isn't AOT-compatible. I'm not a fan of this difference and will be happy to further discuss it.Fixed issues