IDBObjectStore.openCursor()
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.
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
IDBKeyRange
to 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
IDBCursorDirection
telling 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.)
License
© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/idbobjectstore/opencursor