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IDBCursor.advance

The advance() method of the IDBCursor interface sets the number of times a cursor should move its position forward.

Note: This feature is available in Web Workers.

Syntax

cursor.advance(count);

Parameters

count
The number of times to move the cursor forward.

Returns

Void.

Exceptions

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

Exception Description
TransactionInactiveError This IDBCursor's transaction is inactive.
TypeError The value passed into the count parameter was zero or a negative number.
InvalidStateError The cursor is currently being iterated or has iterated past its end.

Example

In this simple fragment we create a transaction, retrieve an object store, then use a cursor to iterate through the records in the object store. Here we use cursor.advance(2) to jump 2 places forward each time, meaning that only every other result will be displayed. advance() works in a similar way to IDBCursor.continue, except that it allows you to jump multiple records at a time, not just always go onto the next record.

Note that in each iteration of the loop, you can grab data from the current record under the cursor object using cursor.value.foo. For a complete working example, see our IDBCursor example (view example live.)

function advanceResult() {
  list.innerHTML = '';
  var transaction = db.transaction(['rushAlbumList'], "readonly");
  var objectStore = transaction.objectStore('rushAlbumList');

  objectStore.openCursor().onsuccess = function(event) {
    var cursor = event.target.result;
    if(cursor) {
      var listItem = document.createElement('li');
      listItem.innerHTML = '<strong>' + cursor.value.albumTitle + '</strong>, ' + cursor.value.year;
      list.appendChild(listItem);  
      cursor.advance(2);
    } else {
      console.log('Every other entry displayed.');
    }
  };
};

Specifications

Specification Status Comment
Indexed Database API
The definition of 'advance()' in that specification.
Recommendation

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 23webkit
24
(Yes) 10 moz
16.0 (16.0)
10, partial 15 7.1
Available in workers (Yes) (Yes) 37.0 (37.0) ? (Yes) ?
Feature Android Android Webview Edge Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile Chrome for Android
Basic support 4.4 (Yes) (Yes) 22.0 (22.0) 1.0.1 10 22 8 (Yes)
Available in workers (Yes) (Yes) (Yes) 37.0 (37.0) (Yes) ? (Yes) ? (Yes)

See also

© 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/API/IDBCursor/advance