Randomize an enum list

Archived Forums Questions & Answers
1

I have an enum list that is going to have a different task each time I run the app. But I do not know how to set the enum list to be random. Can anyone show me how to do it? Here is my code:

using UnityEngine;
using System.Collections;

[ExecuteInEditMode]
public class myTestClass : MonoBehaviour {
public enum MyTasks { task1, task2, task3, task4, task5, task6 }
    MyTasks currentTask = MyTasks.task1;
	public Rect GUIRectWindow, r_msg;
	void Awake()
    {
        //TODO: Initialize stuff here
    }
    void OnGUI()
    {
		// Make a background box
        GUI.Box(GUIRectWindow, "");
        switch (currentCubeTask)
        {
            case CubeTasks.task1:
                drawLabel(r_msg, "This is task 1");
                break;
            case CubeTasks.task2:
                drawLabel(r_msg, "This is task 2");
                break;
            case CubeTasks.task3:
                drawLabel(r_msg, "This is task 3");
                break;
            case CubeTasks.task4:
                drawLabel(r_msg, "This is task 4");
                break;
            case CubeTasks.task5:
                drawLabel(r_msg, "This is task 5");
                break;
            case CubeTasks.task6:
                drawLabel(r_msg, "This is task 6");
                break;
        }
    }
}

3 Answers

3
2

Yeah I got that far but my code still gives me errors for trying to explicitly use the Random.Range for the enum CubeTasks. I just want to know the way to use Random.range on the enum list

 –
3

Under the hood, enums are ints that start at 0 by default (although you can change this). You can cast back and forth, and use Random to select a task randomly:

public enum MyTasks { task1, task2, task3, task4, task5, task6, Count }
MyTasks task = (MyTasks) Random.Range(0, MyTasks.Count);

I added a fake enum “Count” to serve as a shortcut for the Random.Range() function.

However, if you want to shuffle a list of tasks, you’ll have to do a little more. See andeee’s forum thread for some guidance and code. In brief, you’ll fill an array with tasks 1-6 and then shuffle the order of the elements.

Good find but it's still giving me errors. > Error 2 Argument 1: cannot convert > from 'myTestClass.MyTasks' to 'int' > Error 3 Argument 2: cannot convert > from 'myTestClass.MyTasks' to 'int' > Error 1 The best overloaded method > match for > 'UnityEngine.Random.Range(int, int)' > has some invalid arguments I don't think my issue is as complex as it is in the forum.

 –

Try casting to an int: MyTasks task = (MyTasks) Random.Range(0, (int)MyTasks.Count);

 –

@Guts: That worked, thank you!

 –

This only works (casting to an int) if the enumerations do not explicitly set their values for example: enum test { none=0, two=2, four=4, six=6 } If random.range returns 1,3, or 5; it is invalid. The helper code posted with the singleton is a good way to go when that is the case.

 –
4

helper Code:

using UnityEngine;
using System.Collections;
using System.Collections.Generic;

public class EEnum : Singleton<EEnum>
{
	public T GetRandomEnum<T>()
	{
		System.Array A = System.Enum.GetValues(typeof(T));
		T V = (T)A.GetValue(UnityEngine.Random.Range(0,A.Length));
		return V;
	}
}

Usage:

public Prefix 			_Prefix;  

TMP_Name._Prefix = EEnum.Instance.GetRandomEnum();