The upgradeneeded handler is executed when an attempt was made to open a database with a version number higher than its current version.
| Property | Type | Description |
|---|---|---|
target Read only
| EventTarget | The request concerned by this event |
type Read only
| DOMString | The type of event. |
bubbles Read only
| boolean | Does the event normally bubble? |
cancelable Read only
| boolean | Is it possible to cancel the event? |
var req1 = indexedDB.open("addressbook", 999);
req1.onupgradeneeded = function( event ) {
// time for a versionchange transaction
};
// which is equivalent to
req1.addEventListener("upgradeneeded", function( event ) {
// time for a versionchange transaction
});
© 2005–2017 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/Events/upgradeneeded_indexedDB