如何以编程方式获取indexedDB中每个objectStore的当前数据大小？

const databaseName = "myDatabase";
const objectStoreName = "myObjectStore";

function getObjectStoreDataSize() {
  return new Promise((resolve, reject) => {
    const request = indexedDB.open(databaseName);
    
    request.onerror = (event) => {
      reject("Failed to open database");
    };
    
    request.onsuccess = (event) => {
      const db = event.target.result;
      const transaction = db.transaction(objectStoreName, "readonly");
      const objectStore = transaction.objectStore(objectStoreName);
      const cursorRequest = objectStore.openCursor();
      let dataSize = 0;
      
      cursorRequest.onsuccess = (event) => {
        const cursor = event.target.result;
        
        if (cursor) {
          const stringData = JSON.stringify(cursor.value);
          const blob = new Blob([stringData]);
          dataSize += blob.size;
          cursor.continue();
        } else {
          resolve(dataSize);
        }
      };
      
      cursorRequest.onerror = (event) => {
        reject("Failed to open cursor");
      };
    };
    
    request.onupgradeneeded = (event) => {
      const db = event.target.result;
      db.createObjectStore(objectStoreName);
    };
  });
}

getObjectStoreDataSize()
  .then((dataSize) => {
    console.log("ObjectStore data size:", dataSize);
  })
  .catch((error) => {
    console.error(error);
  });