ENUMERATION

PUBLISHED: 9/25/2023

CONTENTS

SECTIONS

• WHAT ARE ENUMS

KEYWORDS

• ENUM --> a value type that represents a list of named integer constants

• CONSTANTS --> fixed values that a program can't change during its execution

GAME BASED EXAMPLES

• GAME BASED EXAMPLE 1 --> Using an enum, define enemy types and assign values to each member

• GAME BASED EXAMPLE 2 --> Using enums, create options for a "Easy", "Normal", "Hard", and "Impossible" difficulty

WHAT ARE ENUMS

A enumeration type, also known as an enum, is a value type that represents a group of constants. It is used to assign constant names to a group of numeric integer values. Enums make constant values easier to read.

An enum is defined using the keyword enum, with all constant names declared inside the curly brackets and separated by a comma.

GAME BASED EXAMPLE 1

OBJECTIVE: Using an enum, define enemy types.

1. DECLARATION | Declare and define an enum for a list of enemy types.
2. VALUES | Each enemy should be assigned an integer value to represent how many points it is worth
3. ACCESS | Access the enemy type
4. CONVERSION | Convert the enemy type to display its point value

STEP ONE | DECLARATION

enum EnemyType
{
    Scout,
    Soldier,
    Sniper,
    Brute
}

STEP TWO | VALUES

By default, if there is no value assigned to the enum members then the compiler will assign an integer value to each member. With the first item having the value 0, the second having the value 1, and so on.

NOTE

You can assign unique values to any number of enum members, but a change in the default value will automatically assign incremental values to the other members.

enum EnemyType
{
    Scout = 5,
    Soldier = 10,
    Sniper = 15,
    Brute = 20
}

STEP THREE | ACCESS

An enum can be accessed using the dot syntax: enum.member

enum EnemyType
{
    Scout = 5,
    Soldier = 10,
    Sniper = 15,
    Brute = 20
}

private void Start()
{
    debug.Log("Wave 1 will consist of the following enemies:")
    debug.Log(EnemyType.Scout)
    
    debug.Log("Wave 2 will consist of the following enemies:")
    debug.Log(EnemyType.Scout)
    debug.Log(EnemyType.Soldier)
}

OUTPUT:

Wave 1 will consist of the following enemies:
Scout

Wave 2 will consist of the following enemies:
Scout
Soldier

STEP FOUR | CONVERSION

To gain access to the integer value from a enum member, you must explicitly convert the member to an int value.

enum EnemyType
{
    Scout = 5,
    Soldier = 10,
    Sniper = 15,
    Brute = 20
}

private void Start()
{
    debug.Log("Wave 1 will consist of the following enemies:");
    debug.Log(EnemyType.Scout);
    
    debug.Log("Wave 2 will consist of the following enemies:");
    debug.Log(EnemyType.Scout);
    debug.Log(EnemyType.Soldier);
    
    int sniper = (int) EnemyType.Sniper;
    debug.Log("Find and destroy Snipers to gain " + sniper + " points.");
    
    int brute = (int) EnemyType.Brute;
    debug.Log("Some enemies are BRUTES. Destroy them to gain and additional " + brute + " points.");
}

OUTPUT:

Wave 1 will consist of the following enemies:
Scout

Wave 2 will consist of the following enemies:
Scout
Soldier

Find and destroy Snipers to gain 15 points.
Some enemies are BRUTES. Destroy them to gain and additional 20 points.

GAME BASED EXAMPLE 2

Enums create logic to be able to create a drop-down menu so a designer/programmer can select a single drop down item within the inspector.

OBJECTIVE: Using Enums, create options for a "Easy", "Normal", "Hard", and "Impossible" difficulty

1. DECLARATION & VALUES | Declare and define an enum for the levels the game will contain.
2. ACCESS | create a variable that will allow the level to be changed from within the Unity Editor
3. SWITCH STATEMENT | Use a switch statement to display which level has been chosen

STEP ONE | DECLARATION & VALUES

Declare and define an enum for the levels the game will contain. Use the default values

enum Difficulty
{
    Easy,         // 0
    Medium,       // 1
    Hard,         // 2
    Impossible    // 3
}

STEP TWO | ACCESS

Create a variable that will allow the level to be changed from within the Unity Editor.

By declaring a public variable of the enum type Level , the program will allow that variable to be modified from within the Unity Editor.

enum Difficulty
{
    Easy,         // 0
    Medium,       // 1
    Hard,         // 2
    Impossible    // 3
}

public Difficulty currentDifficulty;

STEP THREE | SWITCH STATEMENT

Use a switch statement to display which level has been chosen.

enum Difficulty
{
    Easy,         // 0
    Medium,       // 1
    Hard,         // 2
    Impossible    // 3
}

public Difficulty currentDifficulty;

void Update()
{
    switch (currentDifficulty)
    {
        case Difficulty.Easy:
            Debug.Log("Easy Level has been selected");
            break;
        case Difficulty.Normal:
            Debug.Log("Normal Level has been selected");
            break;
        case Difficulty.Hard:
            Debug.Log("Hard Level has been selected");
            break;
        case Difficulty.Impossible:
            Debug.Log("Impossible Level has been selected");
            break;
    }
}