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The IDBVersionChangeEvent
interface of the IndexedDB API indicates that the version of the database has changed, as the result of an IDBOpenDBRequest.onupgradeneeded
event handler function.
Properties
Also inherits properties from its parent, Method
.
IDBVersionChangeEvent.oldVersion
Read only- Returns the old version of the database.
IDBVersionChangeEvent.newVersion
Read only- Returns the new version of the database.
Deprecated properties
IDBVersionChangeEvent.version
Read only-
The new version of the database in a
versionchange
transaction.Warning: While this property is still implemented in older browsers, the latest specification replaces it with the
oldVersion
andnewVersion
attributes. See the compatibility table to know what browsers support them.
Methods
No specific method, but inherits properties from its parent, Method
.
Example
In the following code snippet, we make a request to open a database, and include handlers for the success and error cases. Upon a version change (after an upgradedneeded
event), the success
event will implement the IDBVersionChangeEvent
interface. For a full working example, see our To-do Notifications app (view example live.)
var note = document.querySelector("ul"); // In the following line, you should include the prefixes of implementations you want to test. window.indexedDB = window.indexedDB || window.mozIndexedDB || window.webkitIndexedDB || window.msIndexedDB; // DON'T use "var indexedDB = ..." if you're not in a function. // Moreover, you may need references to some window.IDB* objects: window.IDBTransaction = window.IDBTransaction || window.webkitIDBTransaction || window.msIDBTransaction; window.IDBKeyRange = window.IDBKeyRange || window.webkitIDBKeyRange || window.msIDBKeyRange; // (Mozilla has never prefixed these objects, so we don't need window.mozIDB*) // Let us open version 4 of our database var DBOpenRequest = window.indexedDB.open("toDoList", 4); // these two event handlers act on the database being opened successfully, or not DBOpenRequest.onerror = function(event) { note.innerHTML += '<li>Error loading database.</li>'; }; DBOpenRequest.onsuccess = function(event) { note.innerHTML += '<li>Database initialised.</li>'; // store the result of opening the database in the db variable. This is used a lot later on, for opening transactions and suchlike. db = DBOpenRequest.result; };
Specifications
Specification | Status | Comment |
---|---|---|
Indexed Database API The definition of 'IDBVersionChangeEvent' in that specification. |
Recommendation | Initial definition. |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|
version |
12 webkit |
From 4.0 (2.0) to |
No support | No support | No support |
oldVersion |
23webkit 24 |
10, partial | 15 | 7.1 | |
newVersion |
23webkit 24 |
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 | No support |
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
- IDBDatabase.onversionchange
- Reference example: To-do Notifications (view example live.)