implementing default values in a Model

Question

In a C# MVC application, I have a Model, Customer, which can be retrieved from the database, or created as new.

If I am creating a new Customer what is the proper way to set default values (such as CusotmerLevel defaults to 1)?

Should I have different constructors for a new employee and an employee retrieved from the database, or some other way?

Answer 1

Assuming it's a POCO, I've always found the constructor is fine for establishing default values. I usually take that opportunity to declare things like CreatedDate. When it's retrieved from the database, the public properties will be overridden by the database values anyways.

public class Customer
{
    public Int32 Id { get; set; }
    public Int32 CustomerLevel { get; set; }
    /* other properties */

    public Customer()
    {
        this.CustomerLevel = 1;
    }
}

Update

And, if you're using C# 6.0 check out auto-property initializers:

public class Customer
{
    public Int32 Id { get; set; } = 1;
    public Int32 CustomerLevel { get; set; }
    /* other properties */
}

Answer 2

Use the default constructor, all the ORMs I've tried set values after the constructor is run so it should not interfere.

One alternative method would be:

 var customer = new Customer() { CustomerLevel=1 };