IDBCursor.advance()

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句法
范例
规范
浏览器兼容性
另请参阅
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advance() 方法在 IDBCursor interface sets the num ber of times a cursor should move its position forward.

注意： 此特征可用于 Web 工作者 .

句法

cursor.advance(count);

参数

count

异常

此方法可能引发 DOMException of one of the following types:

异常	描述
`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.

范例

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 ( 实时查看范例 )。

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.');
    }
  };
};

规范

规范	状态	注释
索引数据库 API 2.0 The definition of 'advance()' in that specification.	推荐
索引数据库 API 草案 The definition of 'advance()' in that specification.	推荐

浏览器兼容性

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. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`advance`	Chrome 24 24 不支持 23 — 24 Prefixed Prefixed Implemented with the vendor prefix: webkit	Edge 12	Firefox 16 16 不支持 10 — 16 Prefixed Prefixed Implemented with the vendor prefix: moz	IE 部分支持 10	Opera 15	Safari 7	WebView Android Yes	Chrome Android Yes	Firefox Android 22	Opera Android 14	Safari iOS 8	Samsung Internet Android Yes

图例

完整支持
部分支持
要求使用供应商前缀或不同名称。

另请参阅

使用 IndexedDB
开始事务： IDBDatabase
使用事务： IDBTransaction
设置一系列键： IDBKeyRange
检索并使您的数据改变： IDBObjectStore
使用光标： IDBCursor
参考范例：待办通知 ( 实时查看范例 )。

元数据

最后修改： 2020 年 1 月 22 日

IndexedDB API
IDBCursor
特性
1. direction
2. key
3. primaryKey
4. request
5. source
方法
1. advance()
2. continue()
3. continuePrimaryKey()
4. delete()
5. update()
IndexedDB 相关页面

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句法

参数

异常

范例

规范

浏览器兼容性

图例

另请参阅

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