In Chapter 34, we showed you how to use validation attributes with the model binding feature to ensure that the user submits valid data when creating model objects. The form is shown to the user again if there are any problems with the data, along with a summary of those problems. The user is then able to correct the problems and submit the data again.
In our earlier examples, validation feedback from the server seemed responsive because the browser and the server are on the same device. In a deployed application, it can take several seconds for the browser to submit the form and get the validation errors. There ...