Trouble with Loading Json Files

Problems with Unity “tiny lite” built-in JSON:

In general I highly suggest staying away from Unity’s JSON “tiny lite” package. It’s really not very capable at all and will silently fail on very common data structures, such as bare arrays, tuples, Dictionaries and Hashes and ALL properties.

Instead grab Newtonsoft JSON .NET from the Unity Package Manager (Window → Package Manager).

If you want to avoid the Package Mangler’s UI, just add this to your Packages/manifest.json file:

"com.unity.nuget.newtonsoft-json": "3.0.2",

The former asset store package is now deprecated, as you can see here:

Also, when working with JSON, always be sure to leverage sites like:

https://csharptojson.com

Since you’re working on Load/Save…:

An excellent discussion of loading/saving in Unity3D by Xarbrough:

And another excellent set of notes and considerations by karliss_coldwild:

Loading/Saving ScriptableObjects by a proxy identifier such as name:

When loading, you can never re-create a MonoBehaviour or ScriptableObject instance directly from JSON. The reason is they are hybrid C# and native engine objects, and when the JSON package calls new to make one, it cannot make the native engine portion of the object.

Instead you must first create the MonoBehaviour using AddComponent() on a GameObject instance, or use ScriptableObject.CreateInstance() to make your SO, then use the appropriate JSON “populate object” call to fill in its public fields.

If you want to use PlayerPrefs to save your game, it’s always better to use a JSON-based wrapper such as this one I forked from a fellow named Brett M Johnson on github:

Do not use the binary formatter/serializer: it is insecure, it cannot be made secure, and it makes debugging very difficult, plus it actually will NOT prevent people from modifying your save data on their computers.

Also, just FYI:

If you post a code snippet, ALWAYS USE CODE TAGS:

How to use code tags: Using code tags properly

  • Do not TALK about code without posting it.
  • Do NOT post unformatted code.
  • Do NOT retype code. Use copy/paste properly using code tags.
    - Do NOT post screenshots of code.
    - Do NOT post photographs of code.
  • Do NOT attach entire scripts to your post.
  • ONLY post the relevant code, and then refer to it in your discussion.
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