EditController create/edit POST form handling could be more flexible and/or easier to customize

[ScottMaxson]

Extensions to this class would like to add custom data types, or modify handling of types submitted from (custom) forms more easily. Right now the path is to override the save method, which is OK but even better would be a way to inject special parameter handling by overriding _convertValues or providing a special type-handler to do single point conversion.

[loppear]

Agree it would be nice to have a broader form conversion library in use here, but is there a reason that overriding _convertValues isn't the entry point you want?

Or is this a placeholder that you have a workaround for but eventually we should propose a better API/expression for?

[ScottMaxson]

Current use case is to change handling of the array data type so that it accepts array-type in the request body property (eg using a multi-select or checkbox on the input form).
Expect that some cases where I'd parse json types and do additional validation would be useful in the (near) future.