ASP.NET MVC Entity Framework: Data Annotations

Question

I'm working with Entity Framework with a database-first approach. I already defined the model inside my application. Now I'm working with controllers and views. I used scaffolding in order to create controllers. Now I want to create rows.

Let's say I want to create employees, and let's say the DBA and EF made this possible:

    public partial class TBL_EMPLOYEE
    {
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]
        public TBL_EMPLOYEE()
        {
            this.TBL_EMPLOYEE = new HashSet<TBL_EMPLOYEE>();
        }

        public int EMPLOYEE_ID { get; set; }
        public String CO_WORKER_NUMBER { get; set; }
        public string NAME { get; set; }
        public string LAST_NAME { get; set; }
        public string SALARY { get; set; }
        public string PHONE_NUMBER { get; set; }
        public string EMAIL { get; set; }
        public string { get; set; }

        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
    }

Now, I need a view to create an employee, let's call this view VIEW 1 In this view, the user only needs to specify name and last name values. Both are required.

Now, in this VIEW 1 case I could use the following data annotations attributes in the same class, that'd be:

        [Required]
        public string NAME { get; set; }

        [Required]
        public string LAST_NAME { get; set; }

Now, let's go to the next case. I need another View, let's call this VIEW 2 In this one, the user needs to specify all values for all attributes. All of them are required except for name and last name.

THE REAL QUESTION

How can I use the same model class for both views? The example above here might seem a bit silly and trivial validations but I've been in bigger projects where entities are bigger and the idea of having different ViewModel classes is just so much work.

I've stumbled upon this in my .NET developments, to the point I had to create a ViewModel class per view in order to be specific with what the user needs to input and their validation. Is this the only way?

Answer 1

To avoid duplicating models with minor variations, try this:

https://stackoverflow.com/a/18898112/6850962

Basically, create a base model with data annotations that apply in all situations (eg: DisplayName) and then extend the model for variations (eg: Required attribute).