Finally, a serializable dictionary for Unity! (extracted from System.Collections.Generic)

Unity team, please... I've been waiting for years. Implement serializable dicts.

 

I love your signature!

 

thread bump! Nothin to add and nothing to gain it seems since Unity team does not want to implement this

 

It's the only way. The reason why Unity is called "Unity", is for you guys to unite and copy & paste my signature into your signature. Let's unite as one and do this! #Unity

 

Currently there is a unity serialized dictionary

adding URP you can use UnityEngine.Rendering.SerializedDictionary<T,Y>

and it serializes ina really fancy way, but i encountered some problems with it, not sure why it is in rendering at all

 

Thus is all well and good. I prefer to stick to matched index Lists and Arrays as I can stipulate order and link more than a key value pair.

 

Its 2022, and no sign of serializable Dictionaries from Unity. Maybe we should print t-shirts demanding this basic quality of life feature...

 

I just tought this was by default but then i realized i was using odin UmU

True, lol, isnt there even a place on the roadmap for it?

 

Odin is super nice, but even it fails for serialized dictionary within prefabs variants.

 

The prefabs issue is a Unity issue with their wonky prefab serialisation and their limited API regarding prefabs. Just shunt that sort of data onto scriptable objects.

With respect to no dictionaries in Unity... Unity's serialisation is basic for a reason: it's fast.

It's why the SerializeReference attribute comes with a warning that it comes with additional overhead. And as fast as Odin's serialisation is, Unity's is almost always faster.

So I can understand why it's low priority.

 

I dont think unity will ever add dictionary serialization seeing as version 2022 now comes with the JsonNet library already added. Thats right, you get not one, but two! json serializers with every unity project!

I've just been using JsonNet now for so long even if they did add it to Unity i doubt i'd even bother going back to it. The only real advantage it would provide is editing dictionaries from the inspector.

 

Unfortunately, the serialized dictionary approach presented here is not working with List types (e.g. as values)

 

Well yes, because if you're using the solution on the front of this post you're essentially doing a List<List<T>>, which is not something Unity supports the serialisation of.

You want to use a wrapper class instead, which has the list inside of it.

 

You can create a serializable class with a list inside of it, eg

Code (CSharp):

1. [System.Serializable]
2. public class MyClass
3. {
4.     public List<int> myList = new List<int>();
5. }
6.  
7. public class Main
8. {
9.     // this is serializable and will be editable from the inspector
10.     public List<MyClass> serializableList = new List<MyClass>();
11. }

But if you just need to serialize 2D arrays and such, honestly just use JsonNet, it'll be much cleaner

 

I am unquestionably retarded.
1) Why did I make the save load static?
2) It was right in front of me! The console is spotless! I'll let you know if I get it to work!

My plan is to create a custom class called "Values" that will hold a variety of variables such as tier, skin, and so on. Because the types are simple, such as string and int, I'll make the class serializable.

THANK YOU SO MUCH!

 

It seems like a good idea to have a "don't destroy on load" option.
My first plan was to use the playerprefs approach, but I'm not sure how deserialization works. My dictionary isn't that extensive, but it does contain the enemy type and an approximation of how many of each are needed to spawn, and it's read throughout the spawn process.

 

1) Make wrappers whenever you can. I realise this may sound irritating, but do it where there isn't complete chaos.
2) IMPERATIVELY mark items with SerializeField or System.
This is true whether or not the ISerializationCallbackReceiver interface is being used. Just ALWAYS do that, private/public/internal/protected fields equally. Be VERY clear about your intentions; the serializer appears to abide by these requirements.
3) If a field is marked as non serialised, you may generally do whatever you want with it (as long as it doesn't directly touch the Unity API). However, if you need to change serialised properties, do it all at once. Use arrays that are only set rather than iterating over fields that are NOT marked as non-serialized.
As an illustration, here's how I'd serialise a dictionary:

Code (csharp):

1.  
2. void ISerializationCallbackReceiver.OnBeforeSerialize()
3. _keys equals this.
4. _values = this; keys.ToArray()
5. ToArray(); Values;
6.  

 

Answer
I just extracted the DictionaryTK, TV> code and marked the relevant fields with [SerializeField] to accomplish that. Additionally, it was somewhat refactored and cleaned up (the fields were renamed, the implementation of non-generic interfaces was deleted, and the "hashCode," "next," "key," and "value" from the "Entry" class were factored out and converted to arrays).
The "IsWellKnownEqualityComparer" was one part that I left a remark on because I wasn't really sure about it. I ran some tests, and nothing seemed to change. Please let me know if you genuinely believe it to be crucial.

 

What is this

 

Confusion taking hold. Matched index lists and arrays are much more useful than Dictionaries IMHO.

 

The dictionary works in Unity Editor Mode and Unity Play Mode, but when I build to my Android target device, the dictionary cannot find the value of a key which existed before, both on the target device and in the Unity Editor and Play Mode. So building to the target device somehow changes the a hash value of the key. This problem occurs when I run the ContainsKey() method, I traced the problem down to the following line:

var keys = myDictSerializable.Keys;

bool hasKey = keys.Contains(myExistingKey) // hasKey == true



myDictSerializable.ContainsKey(myExistingKey)



//entering the ContainsKey() method, relevant line:

int hash = _Comparer.GetHashCode(key) & 2147483647 

The hash has changed after building to the target device, e.g. from '104928' to '122816'

So the ContainsKey() method returns false. Anyone knows why this happens and how to fix this?

 

Seems to work perfectly for me! Great job, vexe. People like you that engineer fantastic code and give it to others for free give me faith in humanity.

 

can pls give me 1 expamle ı did get how to use,

ı made a new script and copied the script that contains "[Serializable, DebuggerDisplay("Count = {Count}")]"

after that crate a new script and copied this script

1. [Serializable]
2. public class MyDictionary : SerializableDictionary<string, int> { }
3. 
   
4. public class Test : MonoBehaviour
5. {
6. public MyDictionary dictionary;
7. }

and a get this error

cant add script ,this scripts needs to derive from MonoBehaviour

 

All monobehaviours need to be in their own script assets. Separate the above into two files.

 

Is there a gist of the latest version?