IDBOpenDBRequest: upgradeneeded event
The upgradeneeded
event is fired when an attempt was made to open a database with a version number higher than its current version.
This event is not cancelable and does not bubble.
Syntax
Use the event name in methods like addEventListener()
, or set an event handler property.
addEventListener('upgradeneeded', event => { });
onupgradeneeded = event => { };
Event type
An IDBVersionChangeEvent
. Inherits from Event
.
Event properties
Also inherits properties from its parent, Event
interface.
IDBVersionChangeEvent.oldVersion
Read only-
Returns the old version of the database.
IDBVersionChangeEvent.newVersion
Read only-
Returns the new version of the database.
Examples
This example opens a database and handles the upgradeneeded
event by making any necessary updates to the object store.
// Open the database
const dBOpenRequest = window.indexedDB.open('toDoList', 4);
dBOpenRequest.addEventListener('upgradeneeded', event => {
const db = event.target.result;
console.log(`Upgrading to version ${db.version}`);
// Create an objectStore for this database
var objectStore = db.createObjectStore('toDoList', { keyPath: 'taskTitle' });
// define what data items the objectStore will contain
objectStore.createIndex('hours', 'hours', { unique: false });
objectStore.createIndex('minutes', 'minutes', { unique: false });
objectStore.createIndex('day', 'day', { unique: false });
objectStore.createIndex('month', 'month', { unique: false });
objectStore.createIndex('year', 'year', { unique: false });
});
This is the same example, but uses the onupgradeneeded event handler property.
// Open the database
const dBOpenRequest = window.indexedDB.open('toDoList', 4);
dBOpenRequest.onupgradeneeded = event => {
const db = event.target.result;
console.log(`Upgrading to version ${db.version}`);
// Create an objectStore for this database
var objectStore = db.createObjectStore('toDoList', { keyPath: 'taskTitle' });
// define what data items the objectStore will contain
objectStore.createIndex('hours', 'hours', { unique: false });
objectStore.createIndex('minutes', 'minutes', { unique: false });
objectStore.createIndex('day', 'day', { unique: false });
objectStore.createIndex('month', 'month', { unique: false });
objectStore.createIndex('year', 'year', { unique: false });
};
Browser compatibility
BCD tables only load in the browser