IDBObjectStore.openCursor()

The openCursor() method of the IDBObjectStore interface returns an IDBRequest object, and, in a separate thread, returns a new IDBCursorWithValue object. Used for iterating through an object store with a cursor.

To determine if the add operation has completed successfully, listen for the results’s success event.

Note: This feature is available in Web Workers

Syntax

var request = ObjectStore.openCursor();
var request = ObjectStore.openCursor(query);
var request = ObjectStore.openCursor(query, direction);

Parameters

query Optional

A key or IDBKeyRange to be queried. If a single valid key is passed, this will default to a range containing only that key. If nothing is passed, this will default to a key range that selects all the records in this object store.

direction Optional

An IDBCursorDirection telling the cursor what direction to travel. Valid values are "next", "nextunique", "prev", and "prevunique". The default is "next".

Return value

An IDBRequest object on which subsequent events related to this operation are fired.

Exceptions

This method may raise a DOMException of one of the following types:

Exception Description
InvalidStateError This IDBObjectStore or IDBIndex has been deleted.
TransactionInactiveError This IDBObjectStore's transaction is inactive.
DataError The specified key or key range is invalid.

Example

In this simple fragment we create a transaction, retrieve an object store, then use a cursor to iterate through all the records in the object store:

var transaction = db.transaction("name", "readonly");
var objectStore = transaction.objectStore("name");
var request = objectStore.openCursor();
request.onsuccess = function(event) {
  var cursor = event.target.result;
  if(cursor) {
    // cursor.value contains the current record being iterated through
    // this is where you'd do something with the result
    cursor.continue();
  } else {
    // no more results
  }
};

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
openCursor
23
12
10
10
15
7
≤37
25
22
14
8
1.5

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/IDBObjectStore/openCursor