IDBVersionChangeEvent
The IDBVersionChangeEvent interface of the IndexedDB API indicates that the version of the database has changed, as the result of an onupgradeneeded event handler function.
Note: This feature is available in Web Workers
Constructor
IDBVersionChangeEvent()-
Creates and returns a new
IDBVersionChangeEventobject which is used to represent when a version of the database has changed.
Properties
Also inherits properties from its parent, Event interface.
IDBVersionChangeEvent.oldVersionRead only-
Returns the old version of the database.
IDBVersionChangeEvent.newVersionRead only-
Returns the new version of the database.
Deprecated properties
IDBVersionChangeEvent.versionRead only-
The new version of the database in a
versionchangetransaction.Warning: While this property is still implemented in older browsers, the latest specification replaces it with the
oldVersionandnewVersionattributes. See the compatibility table to know what browsers support them.
Methods
No specific method, but inherits properties from its parent, Event interface.
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 upgradeneeded 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 initialized.</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 |
|---|
| Indexed Database API 3.0 # events |
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 - IDBDatabase.onversionchange
- Reference example: To-do Notifications (view example live.)