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The source
read-only property of the IDBRequest
interface returns the source of the request, such as an Index or an object store. If no source exists (such as when calling indexedDB.open
), it returns null.
Syntax
var IDBIndex = request.source; var IDBCursor = request.source; var IDBObjectStore = request.source;
Value
An object representing the source of the request, such as an IDBIndex
, IDBObjectStore
or IDBCursor
.
Example
The following example requests a given record title, onsuccess
gets the associated record from the IDBObjectStore
(made available as objectStoreTitleRequest.result
), updates one property of the record, and then puts the updated record back into the object store in another request. The source of the 2nd request is logged to the developer console. For a full working example, see our To-do Notifications app (view example live.)
var title = "Walk dog"; // Open up a transaction as usual var objectStore = db.transaction(['toDoList'], "readwrite").objectStore('toDoList'); // Get the to-do list object that has this title as its title var objectStoreTitleRequest = objectStore.get(title); objectStoreTitleRequest.onsuccess = function() { // Grab the data object returned as the result var data = objectStoreTitleRequest.result; // Update the notified value in the object to "yes" data.notified = "yes"; // Create another request that inserts the item // back into the database var updateTitleRequest = objectStore.put(data); // Log the source of this request console.log("The source of this request is " + updateTitlerequest.source); // When this new request succeeds, run the displayData() // function again to update the display updateTitleRequest.onsuccess = function() { displayData(); }; };
Specifications
Specification | Status | Comment |
---|---|---|
Indexed Database API The definition of 'source' in that specification. |
Recommendation | |
Indexed Database API 2.0 The definition of 'source' in that specification. |
Editor's Draft |
Browser compatibility
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | 23webkit 24 (unprefixed) |
(Yes) | 10 moz 16.0 (16.0) |
10, partial | 15 | 7.1 |
Available in workers | (Yes) | ? | 37.0 (37.0) | ? | (Yes) | ? |
Indexed Database 2.0 | 58 | ? | ? | ? | 45 | ? |
Feature | Android Webview | Chrome for Android | Edge | Firefox Mobile (Gecko) | Firefox OS | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | 22.0 (22.0) | 1.0.1 | 10 | 22 | 8 |
Available in workers | (Yes) | (Yes) | ? | 37.0 (37.0) | (Yes) | ? | (Yes) | ? |
Indexed Database 2.0 | 58 | 58 | ? | ? | ? | ? | 45 | ? |
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.)