Validation doesn't automatically traverse members

[danroth27]

Validation doesn't automatically traverse the members of something so you have to manually add validation support for any satellite objects you want validated.

Example: https://github.com/rynowak/ComponentFunTime/blob/master/Components/Shared/EmployeeEditor.razor#L85

[mrpmorris]

@danroth27

Possible solution:
In InputBase<T>.set_FieldIdentifier execute EditContext.GetFieldState(value, true)

This will add the field state to the EditContext and ensure it is validated.

[pranavkm]

Moving this out of the backlog. We should consider doing something about this in 3.1 since the experience is fairly poor right now.

[mkArtakMSFT]

Summary of an in-person discussion:

• Create an experimental package with a solution for 3.1
• Document this and require the usage of the new package for this to work
• Revisit in 5.0, based on whether corefx add a native support for this or not

[mrpmorris]

All you need to do is have InputBase ensure it has an entry in the EditContext when its EditContext changes. That will ensure only the items being edited are validated. This should be a minimum requirement.

If you also want to provide the ability to validate a whole object regardless of which properties have associated edits, please put a parameter on the validator that allows the user to disable it.

Also, please make the traversal code part of EditContext and not DataAnnoticationsValidator - so other validation frameworks can use it too.