IDBVersionChangeEvent

BaselineWidely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

Note: This feature is available inWeb Workers.

TheIDBVersionChangeEvent interface of theIndexedDB API indicates that the version of the database has changed, as the result of anonupgradeneeded event handler function.

Constructor

IDBVersionChangeEvent(): Creates and returns a newIDBVersionChangeEvent object which is used to represent when a version of the database has changed.

Instance 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.

Instance methods

No specific method, but inherits methods from its parent,Event interface.

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 anupgradeneeded event), thesuccess event will implement theIDBVersionChangeEvent interface. For a full working example, see ourTo-do Notifications app (view example live).

const note = document.querySelector("ul");// Let us open version 4 of our databaseconst DBOpenRequest = window.indexedDB.open("toDoList", 4);// these two event handlers act on the database being opened successfully, or notDBOpenRequest.onerror = (event) => {  note.appendChild(document.createElement("li")).textContent =    "Error loading database.";};DBOpenRequest.onsuccess = (event) => {  note.appendChild(document.createElement("li")).textContent =    "Database initialized.";  // store the result of opening the database in the db variable. This is used a lot later on, for opening transactions and suchlike.  const db = DBOpenRequest.result;};