IDBEnvironment - Web APIs 编辑

Obsolete

This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.

Important: The indexedDB property that was previously defined in this mixin is instead now WindowOrWorkerGlobalScope.indexedDB (that is, defined as a member of the WindowOrWorkerGlobalScope mixin).

The IDBEnvironment helper of the IndexedDB API contains the indexedDB property, which provides access to IndexedDB functionality. It is the top level IndexedDB interface implemented by the window and Worker objects.

Note:

Properties

IDBEnvironment.indexedDB Read only

Provides a mechanism for applications to asynchronously access capabilities of indexed databases; contains an IDBFactory object.

Example

The following code creates a request for a database to be opened asychronously, after which the database is opened when the request's onsuccess handler is fired:

var db;
function openDB() {
 var DBOpenRequest = window.indexedDB.open("toDoList");
 DBOpenRequest.onsuccess = function(e) {
   db = DBOpenRequest.result;
 };
}

Browser compatibility

BCD tables only load in the browser

See also

• Using IndexedDB
• Starting transactions: IDBDatabase
• Using transactions: IDBTransaction
• Setting a range of keys: IDBKeyRange
• Retrieving and making changes to your data: IDBObjectStore
• Using cursors: IDBCursor
• Reference example: To-do Notifications (view example live.)