IDBObjectStore.getAllKeys() - Web APIs 编辑

The getAllKeys() method of the IDBObjectStore interface returns an IDBRequest object retrieves record keys for all objects in the object store matching the specified parameter or all objects in the store if no parameters are given.

If a value is successfully found, then a structured clone of it is created and set as the result of the request object.

This method produces the same result for:

• a record that doesn't exist in the database
• a record that has an undefined value

To tell these situations apart, you need to call the openCursor() method with the same key. That method provides a cursor if the record exists, and no cursor if it does not.

Syntax

var request = objectStore.getAllKeys();
var request = objectStore.getAllKeys(query);
var request = objectStore.getAllKeys(query, count);

Parameters

query Optional

A value that is or resolves to an IDBKeyRange.

count Optional

Specifies the number of values to return if more than one is found. If it is lower than 0 or greater than 232-1 a TypeError exception will be thrown.

Return value

An IDBRequest object on which subsequent events related to this operation are fired.

Exceptions

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

Specifications

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.)