Using a dictionary in unity without serializing it.

This is an example of how to use a dictionary in Unity without having to serialize the dictionary itself.

Code (CSharp):

1. public class DictionaryExampleUsage : MonoBehaviour
2. {
3.     [System.Serializable]
4.     public class ObjectIDPair
5.     {
6.         public string ID;
7.         public GameObject gameObject;
8.         public string otherDataExample;
9.         public bool someOtherData;
10.     }
11.     public List<ObjectIDPair> dataPairs;
12.     public Dictionary<string, ObjectIDPair> realDictionary;
13.     void Awake()
14.     {
15.         Init();
16.     }
17.     void Init()
18.     {
19.         realDictionary = new Dictionary<string, ObjectIDPair>();
20.         foreach (ObjectIDPair pair in dataPairs)
21.             realDictionary.Add(pair.ID, pair);
22.     }
23. }

 

There are some drawbacks:
- depending on the amount of data, this can be utterly slow on startup
- you have the data in memory twice, waste of memory, depending on the amount of data this can be unacceptable

 

This is a standard pattern I use all the time. If it's a small amount of data, the loading phase should be negligible. I believe you could also get around "having two copies in memory" by clearing the list after you load the data into the dictionary (this will need to be garbage collected obviously).

 

What is the drawback to serializing the dictionary?

 

This is mostly for convenience purposes. It is far more efficient to use a dictionary, but Unity doesn't serialize dictionaries, so the only way to use them without serializing it yourself and saving/loading the data when you need to edit it. This is a way to create a dictionary of something from a List or Array in inspector, just convenient is all.