guides

Save & load

One call each way, JSON on disk, and enough engineering underneath that a crash mid-write can't eat a save.

The one-liners

Save / load any controller

inventory.SaveInventory();              // default file for this inventory type
inventory.LoadInventory();

inventory.SaveInventory("checkpoint_3"); // or name the file yourself
inventory.LoadInventory("checkpoint_3");

The same pair exists on grid, slot, hotbar, and equipment controllers. Each inventory type writes into its own subfolder:

On disk

text

{Application.persistentDataPath}/InventorySaves/
├── Player/
│   ├── inventory_player.json       ← grid default
│   ├── slotinventory_player.json   ← slot/hotbar default
│   ├── equipment_player.json       ← equipment default
│   └── autosave_player.json        ← written by Auto Save
├── Shop/…
└── Stash/…

# Windows: %userprofile%/AppData/LocalLow/<Company>/<Product>/InventorySaves

What gets saved

Per item: the ItemID, grid position (or slot index), rotation, stack count, condition, and custom name — plus the grid dimensions and a format version for the file itself. Item definitions are not serialized; they're re-resolved from the ID on load.

// heads up

Items must be resolvable at load time. The default lookup scans Resources.LoadAll<ItemData>(""), so ItemData assets belong under a Resources/ folder and need unique IDs — a duplicate ID means "first found wins." An item whose ID can't be resolved is skipped silently.

Using Addressables or a custom catalog instead

using InventorySystem;

// Replace the Resources scan with your own lookup (per controller family):
SlotInventoryController.ItemDataResolver = id => MyItemCatalog.Find(id);
EquipmentController.ItemDataResolver     = id => MyItemCatalog.Find(id);

// Created ItemData at runtime? Invalidate the session cache:
ItemDataCache.Clear();

Crash-safe by construction

Every write is atomic, and every load self-heals:

Guarantee	Description
Atomic writes	Data goes to a `.tmp` file first, the previous save is demoted to `.bak`, then the temp is promoted. A crash mid-write leaves the old save intact.
Backup recovery	If the live `.json` is missing, empty, or corrupted, loading falls back to the `.bak` automatically (with a console warning).
Version migration	v1-format saves from the original release load transparently; files from a newer asset version log a warning and load best-effort.
Hostile-data sanitizing	Corrupted fields are clamped on load (stack counts below 1 become 1, negative positions reset); items that no longer fit the current grid are relocated to free cells or skipped with a log.

Auto-save & timestamped saves

Tick Auto Save on any controller and it writes autosave_<type>.json every Auto Save Interval seconds (default 30) while playing. For manual checkpoints, the controller's context menu (⋮) offers Save (Timestamped) — files like player_20260716_143012.json — and Load Most Recent.

Managing save files from code

SaveSystem utilities

using InventorySystem;

var saves = new SaveSystem();            // default directory

string[] files = saves.GetSaveFiles();   // names, no extension
bool ok    = saves.SaveFileExists("checkpoint_3");
var info   = saves.GetSaveFileInfo("checkpoint_3");  // times + size
saves.CreateBackup("checkpoint_3");      // → checkpoint_3_backup.json
saves.DeleteSave("checkpoint_3");        // also removes .bak/.tmp companions