Blazor validation for custom class

[Themikuma]

I'm testing out Blazor and I've run into a validation issue. When validating a simple class I can just use annotations. If I have my own custom class inside though validation doesn't run for everything inside my custom class. The issue seems to be specific to Blazor since I can use this validation in ASP. I've got all the details in this Stack Overflow question https://stackoverflow.com/questions/56447004/blazor-validation-for-custom-class

Is this a platform limitation or am I just doing something wrong?

[danroth27]

Hi @Themikuma. Thanks for trying out Blazor!
By default we only validate the data annotations on the top level properties. We understand though that it's pretty common to want to validate the entire graph and we should document how best to do this. We will first need to look into what we think the best approach is.

[JeroMiya]

Just want to add that this also affects models annotated with the ModelMetadataType attribute. This is typical of scenarios where you would add model metadata to the partial classes generated by the Entity Framework database-first scaffolding. Although the best practice would be to have a separate DTO model, with conversions to/from the Entity Framework models, this is often overkill for smaller apps.

[danroth27]

I believe this is a duplicate of #10526.