Save data

The save global: get/set/delete, save slots, and flushing writes.

#Overview

save is a global backed by IndexedDB — the way to make a game remember things across page refreshes and browser restarts, unlike global (see Timers, state & messaging), which resets on every reload.

#Basic reads and writes

save.set("highScore", 4200);
var best = save.get("highScore") ?? 0;
save.has("checkpoint");
save.delete("temporaryBuff");
save.keys(); // every key currently stored
save.clear(); // wipe the current slot

#Save slots

await save.load("slot2"); // switch to a different save file
save.slot; // the currently active slot name
save.listSlots();
save.deleteSlot("slot3");

#Flushing & readiness

save.isReady reflects whether the store has finished its initial load from IndexedDB. Writes are coalesced and flushed asynchronously; call save.flushNow() if you need a write to be durably committed before doing something else (e.g. right before scene.load() on a level transition). save.onError(callback) registers a handler for storage failures (e.g. a full or blocked IndexedDB).

#Example: persistent high score

function onDestroy() {
  var best = save.get("highScore") ?? 0;
  if (global.score > best) save.set("highScore", global.score);
}