// 🔸 app.sheetByName()sheetByName(name) {constss=app.spreadsheet;let sheet =ss.getSheetByName(name);// if no such sheet, append a new one.if(sheet ===null){ let i =ss.getNumSheets(); // 目前的有幾頁 sheet =ss.insertSheet(name, i); // 插入最後面 (⭐️ will activate automatically) }sheet.activate(); // ⭐️ activate before returning sheet.__proto__=app.sheetPrototype; // ⭐️ extend sheet return sheet; },