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.
js
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.
js
// 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
const 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.
js
// 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
const 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 });
};
Specifications
Specification |
---|
Indexed Database API 3.0 # eventdef-idbopendbrequest-upgradeneeded |
Browser compatibility
BCD tables only load in the browser