Create and use Intellenum enums

The tutorial on "your first enum" introduced you to some of the different ways to create an Intellenum.

In this how-to article, we'll explore the rest. The different ways to create instances are:

Field declarations
the Member attribute
the Members (plural) attribute
The Member method
The Members (plural) method

Let's look at each way:

Field declarations

[Intellenum<string>] 
public partial class CustomerType
{
    public static readonly CustomerType Standard, Silver, Gold;
}

This produces an instance with three members.

Console.WriteLine(CustomerType.Standard); // "Standard"
Console.WriteLine(CustomerType.Silver); // "Silver"
Console.WriteLine(CustomerType.Gold); // "Gold"

You can also use different values, e.g.

[Intellenum<string>]
public partial class CustomerType
{
    public static readonly CustomerType 
        Standard = new("STD"), 
        Silver = new("SLVR"), 
        Gold = new ("GLD");
}

The above examples are for enums based on string. The values are defaulted to be the same as name.

For int-based enums, values are defaulted start at zero and increment by one:

[Intellenum<int>]
public partial class CustomerType
{
    public static readonly CustomerType Standard, Silver, Gold;
}

This produces an instance with three members.

Console.WriteLine(CustomerType.Standard); // 0
Console.WriteLine(CustomerType.Silver); // 1
Console.WriteLine(CustomerType.Gold); // 2

Attributes

You can use attributes to declare members, e.g.

[Intellenum<string>]
[Members("Standard, Gold, Silver")]
public partial class CustomerType;

... or individually

[Intellenum<string>]
[Member("Standard")]
[Member("Gold")]
[Member("Silver")]
public partial class CustomerType;

Static constructors

You can declare members via the Members and Member methods from a static constructor:

[Intellenum<string>
public partial class CustomerType
{
    static CustomerType() => Members("Standard, Silver, Gold");
}

Last modified: 12 September 2024