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.

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.textContent = '';
  const transaction = db.transaction(['rushAlbumList'], "readonly");
  const objectStore = transaction.objectStore('rushAlbumList');

  objectStore.openCursor().onsuccess = function(event) {
    const cursor = event.target.result;
    if(cursor) {
      const 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

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
advance
23
12
10
10
15
7
≤37
Yes
22
14
8
Yes

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/IDBCursor/advance