// server side full validation private void ValidateContact(ContactModel contact) { contact.ClearErrors(); if (string.IsNullOrEmpty(contact.Name)) { contact.AddError(nameof(contact.Name), "Name is required"); } if (string.IsNullOrEmpty(contact.Phone)) { contact.AddError(nameof(contact.Phone), "Phone is required"); } if (string.IsNullOrEmpty(contact.Email)) { contact.AddError(nameof(contact.Email), "Email is required"); } else { if (!contact.Email.Contains("@")) { contact.AddError(nameof(contact.Email), "Not valid email"); } } }