IndexedDB 批量删除与空间回收实践

概述批量删除需保证事务可靠并反馈进度。本文给出最小实现。批量删除function openDB(name) { return new Promise((resolve, reject) => { const r = indexedDB.open(name, 1); r.onupgradeneeded = () => { const db = r.result; if (!db.objectStoreNames.contains('items')) db.createObjectStore('items', { keyPath:'id' }); }; r.onsuccess = () => resolve(r.result); r.onerror = () => reject(r.error); }); } async function bulkDelete(predicate, onProgress) { const db = await openDB('del'); const tx = db.transaction('items','readwrite'); const s = tx.objectStore('items'); const req = s.openCursor(); let total = 0, done = 0; const allKeys = []; await new Promise((res, rej) => { req.onsuccess = e => { const c = e.target.result; if (c) { total++; if (predicate(c.value)) allKeys.push(c.primaryKey); c.continue(); } else res(); }; req.onerror = () => rej(req.error); }); for (const k of allKeys) { s.delete(k); done++; onProgress && onProgress(done, total); } await new Promise((res, rej) => { tx.oncomplete = res; tx.onerror = () => rej(tx.error); }); db.close(); }