The openCursor() method of the IDBObjectStore interface returns an IDBRequest object, and, in a separate thread, returns a new IDBCursorWithValue object. Used for iterating through an object store with a cursor.
To determine if the add operation has completed successfully, listen for the results’s success event.
Note: This feature is available in Web Workers.
Syntax
var request = ObjectStore.openCursor(optionalKeyRange, optionalDirection);
Returns
An IDBRequest object on which subsequent events related to this operation are fired.
Exceptions
This method may raise a DOMException of one of the following types:
| Exception | Description |
|---|---|
InvalidStateError |
This IDBObjectStore or IDBIndex has been deleted. |
TransactionInactiveError |
This IDBObjectStore's transaction is inactive. |
DataError |
The specified key or key range is invalid. |
Example
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:
var transaction = db.transaction("name", "readonly");
var objectStore = transaction.objectStore("name");
var request = objectStore.openCursor();
request.onsuccess = function(event) {
var cursor = event.target.result;
if(cursor) {
// cursor.value contains the current record being iterated through
// this is where you'd do something with the result
cursor.continue();
} else {
// no more results
}
};
Parameters
- range Optional
- A key or
IDBKeyRangeto be queried. If a single valid key is passed, this will default to a range containing only that key. If nothing is passed, this will default to a key range that selects all the records in this object store. - direction Optional
- An
IDBCursorDirectiontelling the cursor what direction to travel. Defaults to "next".
Specification
| Specification | Status | Comment |
|---|---|---|
| Indexed Database API The definition of 'openCursor' in that specification. |
Editor's Draft |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|
| Basic support | 23webkit 24 |
10 moz 16.0 (16.0) |
10, partial | 15 | 7.1 |
| Available in workers | (Yes) | 37.0 (37.0) | ? | (Yes) | ? |
| Feature | Android | Firefox Mobile (Gecko) | Firefox OS | IE Phone | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|
| Basic support | 4.4 | 22.0 (22.0) | 1.0.1 | 10 | 22 | 8 |
| Available in workers | (Yes) | 37.0 (37.0) | (Yes) | ? | (Yes) | ? |
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 example live.)