public static ErrorResponse CreateDynamicValidation() { var factory = new ErrorFactory(); var modelStateDictionary = new ModelStateDictionary(); modelStateDictionary.AddModelError("Property1", "Some validation error."); modelStateDictionary.AddModelError("Property1", "Some more validation error."); modelStateDictionary.AddModelError("Property2", "This is bad!"); modelStateDictionary.AddModelError("Property3", "This is very bad!"); modelStateDictionary.AddModelError("Property4", "This is even worst!"); var error = factory.CreateErrorFor(new SerializableError(modelStateDictionary)); return(new ErrorResponse(error)); }