IDBObjectStore.deleteIndex()

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规范
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deleteIndex() 方法在 IDBObjectStore interface destroys the index with the specified name in the connected database, used during a version upgrade.

Note that this method must be called only from a VersionChange transaction mode callback. Note that this method synchronously modifies the IDBObjectStore.indexNames 特性。

注意： 此特征可用于 Web 工作者 .

句法

objectStore.deleteIndex(indexName);

参数

indexName

返回值

undefined

异常

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

异常	描述
`InvalidStateError`	Occurs if the method was not called from a `versionchange` transaction mode callback.
`TransactionInactiveError`	Occurs if the transaction this `IDBObjectStore` belongs to is not active (e.g. has been deleted or removed.) In Firefox previous to version 41, an `InvalidStateError` was raised in this case as well, which was misleading; this has now been fixed (see bug 1176165 )。
`NotFoundError`	Occurs if there is no index with the given name (case-sensitive) in the database.

范例

In the following example you can see the IDBOpenDBRequest.onupgradeneeded handler being used to update the database structure if a database with a higher version number is loaded. IDBObjectStore.createIndex is used to create new indexes on the object store, after which we delete the unneeded old indexes with deleteIndex() . For a full working example, see our 待办通知 app ( 实时查看范例 )。

var db;
// Let us open our database
var DBOpenRequest = window.indexedDB.open("toDoList", 4);
// these two event handlers act on the database being opened successfully, or not
DBOpenRequest.onerror = function(event) {
  note.innerHTML += '<li>Error loading database.</li>';
};
DBOpenRequest.onsuccess = function(event) {
  note.innerHTML += '<li>Database initialised.</li>';
  // store the result of opening the database in the db variable. This is used a lot below
  db = this.result;
  // Run the displayData() function to populate the task list with all the to-do list data already in the IDB
  displayData();
};
// This event handles the event whereby a new version of the database needs to be created
// Either one has not been created before, or a new version number has been submitted via the
// window.indexedDB.open line above
//it is only implemented in recent browsers
DBOpenRequest.onupgradeneeded = function(event) {
  var db = this.result;
  db.onerror = function(event) {
    note.innerHTML += '<li>Error loading database.</li>';
  };
  // 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 });
  objectStore.createIndex("notified", "notified", { unique: false });
  objectStore.deleteIndex("seconds");
  objectStore.deleteIndex("contact");
};

规范

规范	状态	注释
索引数据库 API 2.0 The definition of 'deleteIndex()' in that specification.	推荐
索引数据库 API 草案 The definition of 'deleteIndex()' 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
`deleteIndex`	Chrome 24 24 23 — 57 Prefixed Prefixed Implemented with the vendor prefix: webkit	Edge 12	Firefox 16 16 10 — 16 Prefixed Prefixed Implemented with the vendor prefix: moz	IE 部分支持 10	Opera 15	Safari 7	WebView Android Yes Yes ? — 57 Prefixed Prefixed Implemented with the vendor prefix: webkit	Chrome Android 25 25 25 — 57 Prefixed Prefixed Implemented with the vendor prefix: webkit	Firefox Android 22	Opera Android 14	Safari iOS 8	Samsung Internet Android 1.5 1.5 1.5 — 7.0 Prefixed Prefixed Implemented with the vendor prefix: webkit

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
IDBObjectStore
特性
方法
1. add()
2. clear()
3. count()
4. createIndex()
5. delete()
6. deleteIndex()
7. get()
8. getAll()
9. getAllKeys()
10. getKey()
11. index()
12. openCursor()
13. openKeyCursor()
14. put()
IndexedDB 相关页面

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句法

参数

返回值

异常

范例

规范

浏览器兼容性

图例

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