IndexedDB blocked 与 versionchange 多标签页升级协调

`title: IndexedDB blocked 与 versionchange 多标签页升级协调``categories: Web 开发/前端/数据管理``keywords: IndexedDB,blocked,versionchange,升级,多标签页``description: 在数据库升级时处理 blocked 与 versionchange 事件，协调多标签页关闭与重连，保障模式迁移与数据一致性。`协调示例function openDB(name, version) { return new Promise((resolve, reject) => { const req = indexedDB.open(name, version); req.onblocked = () => { /* 提示其他标签页关闭或刷新 */ }; req.onupgradeneeded = () => { /* 迁移模式 */ }; req.onsuccess = () => { const db = req.result; db.onversionchange = () => { db.close(); /* 提示刷新以连接新版本 */ }; resolve(db); }; req.onerror = () => reject(req.error); }); }