IDBRequest: error event

The error handler is executed when an error caused a request to fail.

Bubbles Yes
Cancelable No
Interface Event
Event handler property onerror

Examples

This example opens a database and tries to add a record, listening for the error event for the add() operation (this will occur if, for example, a record with the given taskTitle already exists):

// Open the database
const DBOpenRequest = window.indexedDB.open('toDoList', 4);

DBOpenRequest.addEventListener('upgradeneeded', 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.addEventListener('success', event => {
  const db = DBOpenRequest.result;

  // open a read/write db transaction, ready for adding the data
  const transaction = db.transaction(['toDoList'], 'readwrite');
  const objectStore = transaction.objectStore('toDoList');
  const newItem = { taskTitle: 'my task', hours: 10, minutes: 10, day: 10, month: 'January', year: 2020 };

  const objectStoreRequest = objectStore.add(newItem);
  objectStoreRequest.addEventListener('error', () => {
    console.log(`Error adding new item: ${newItem.taskTitle}`);
  });
});

The same example, using the onerror property instead of 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 => {
  const db = DBOpenRequest.result;

  // open a read/write db transaction, ready for adding the data
  const transaction = db.transaction(['toDoList'], 'readwrite');
  const objectStore = transaction.objectStore('toDoList');
  const newItem = { taskTitle: 'my task', hours: 10, minutes: 10, day: 10, month: 'January', year: 2020 };

  const objectStoreRequest = objectStore.add(newItem);
  objectStoreRequest.onerror = () => {
    console.log(`Error adding new item: ${newItem.taskTitle}`);
  };
};

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
error eventChrome Full support 24
Full support 24
Full support 23
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Edge Full support 12Firefox Full support 16
Full support 16
No support 10 — 16
Prefixed
Prefixed Implemented with the vendor prefix: moz
IE Full support 10
Notes
Full support 10
Notes
Notes partial
Opera Full support 15Safari Full support 7WebView Android Full support YesChrome Android Full support YesFirefox Android Full support 22Opera Android Full support 14Safari iOS Full support 8Samsung Internet Android Full support Yes

Legend

Full support  
Full support
See implementation notes.
See implementation notes.
Requires a vendor prefix or different name for use.
Requires a vendor prefix or different name for use.

See also