在ASP.NET Core中有两种方法可以进行自定义模型验证:

There are two ways to do custom model validation in ASP.NET Core:

• 从ValidationAttribute子类化的自定义属性.当您要将自定义业务逻辑应用于具有属性的特定模型属性时，这很有用.
• 实施IValidatableObject进行类级验证.如果您需要一次对整个模型进行验证，请改用此方法.

• A custom attribute subclassed from ValidationAttribute. This is useful when you want to apply custom business logic to a particular model property with an attribute.
• Implementing IValidatableObject for class-level validation. Use this instead when you need to do validation on an entire model at once.

文档都有这两个例子.在您的情况下，IValidatableObject可能是***的方法.

The documentation has examples of both. In your case, IValidatableObject would probably be the best approach.