IDBCursor: source property
The source
read-only property of the
IDBCursor
interface returns the IDBObjectStore
or
IDBIndex
that the cursor is iterating over. This function never returns
null or throws an exception, even if the cursor is currently being iterated, has
iterated past its end, or its transaction is not active.
Note: This feature is available in Web Workers
Value
The IDBObjectStore
or IDBIndex
that the cursor is
iterating over.
Examples
In this simple fragment we create a transaction, retrieve an object store, then use a
cursor to iterate through all the records in the object store. Within each iteration we
log the source of the cursor, which will log our IDBObjectStore
object to
the console, something like this:
json
IDBObjectStore {autoIncrement: false, transaction: IDBTransaction, indexNames: DOMStringList, keyPath: "albumTitle", name: "rushAlbumList"…}
The cursor does not require us to select the data based
on a key; we can just grab all of it. Also note that in each iteration of the loop,
you can grab data from the current record under the cursor object using cursor.value.foo
. For a complete working example, see our IDBCursor example (View the example live).
js
function displayData() {
const transaction = db.transaction(["rushAlbumList"], "readonly");
const objectStore = transaction.objectStore("rushAlbumList");
objectStore.openCursor().onsuccess = (event) => {
const cursor = event.target.result;
if (cursor) {
const listItem = document.createElement("li");
listItem.textContent = `${cursor.value.albumTitle}, ${cursor.value.year}`;
list.appendChild(listItem);
console.log(cursor.source);
cursor.continue();
} else {
console.log("Entries all displayed.");
}
};
}
Specifications
Specification |
---|
Indexed Database API 3.0 # ref-for-dom-idbcursor-source① |
Browser compatibility
BCD tables only load in the browser
See also
- Using IndexedDB
- Starting transactions:
IDBDatabase
- Using transactions:
IDBTransaction
- Setting a range of keys:
IDBKeyRange
- Retrieving and making changes to your data:
IDBObjectStore
- Using cursors:
IDBCursor
- Reference example: To-do Notifications (View the example live).