> For the complete documentation index, see [llms.txt](https://giantgrey.gitbook.io/flowreactor/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://giantgrey.gitbook.io/flowreactor/api/frvariables/frenum.md).

# FREnum

{% hint style="info" %}
FlowReactor comes with a generic enum type which can be used for your custom nodes and Blackboard variables.
{% endhint %}

**Example**

```csharp
// Define your enum like this:
public enum MyEnum
{
  A,
  B,
  C
}
 
// To make sure we can select the enum from the Blackboard we need to add the FRVariableAttribute.
// Create a custom class and inherit from FREnum and set your custom enum as type
[FRVariableAttribute(Name = "MyEnum")]
public class MyCustomEnum : FREnum<myenum>{}</myenum>
 
// Now we can create our new enum variable field like this.
// Important: You have to create a new instance of your enum by using "new"
public MyCustomEnum testEnum = new MyCustomEnum();
```