The blocked
handler is executed when an open connection to a database is blocking a versionchange
transaction on the same database.
Bubbles | No |
Cancelable | No |
Interface | IDBVersionChangeEvent
|
Event handler property | onblocked
|
Examples
Using addEventListener()
:
// Open the database const DBOpenRequest = window.indexedDB.open('toDoList', 4); DBOpenRequest.onupgradeneeded = (event) => { const db = event.target.result; db.onerror = () => { console.log('Error creating database'); }; // 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 }); }; DBOpenRequest.onsuccess = (event) => { // Let's try to open the same database with a higher revision version const req2 = indexedDB.open('toDoList', 5); // In this case the onblocked handler will be executed req2.addEventListener('blocked', () => { console.log('Request was blocked'); }); };
Using the onblocked
property:
// Open the database const DBOpenRequest = window.indexedDB.open('toDoList', 4); DBOpenRequest.onupgradeneeded = (event) => { const db = event.target.result; db.onerror = () => { console.log('Error creating database'); }; // 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 }); }; DBOpenRequest.onsuccess = (event) => { // Let's try to open the same database with a higher revision version const req2 = indexedDB.open('toDoList', 5); // In this case the onblocked handler will be executed req2.onblocked = () => { console.log('Request was blocked'); }; };
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
blocked event
|
Chrome Full support 24 Full support 24 No support 23 — 57 Prefixed' Implemented with the vendor prefix: webkit |
Edge
Full support 12 |
Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz |
IE
Partial support 10 |
Opera
Full support 15 |
Safari
Full support 7 |
WebView Android Full support Yes Full support Yes No support ? — 57 Prefixed' Implemented with the vendor prefix: webkit |
Chrome Android Full support 25 Full support 25 No support 25 — 57 Prefixed' Implemented with the vendor prefix: webkit |
Firefox Android
Full support 22 |
Opera Android
Full support 14 |
Safari iOS
Full support 8 |
Samsung Internet Android Full support 1.5 Full support 1.5 No support 1.5 — 7.0 Prefixed' Implemented with the vendor prefix: webkit |
Legend
- Full support
- Full support
- Partial support
- Partial support
- Requires a vendor prefix or different name for use.'
- Requires a vendor prefix or different name for use.
See also
- Using IndexedDB
onblocked
event handler property
IDBOpenDBRequest: blocked event by Mozilla Contributors is licensed under CC-BY-SA 2.5.