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• 方法概述
• 属性
• 常量
• 方法
• 相关话题

草案
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重要 : The synchronous version of the IndexedDB API was originally intended for use only with Web 工作者 , and was eventually removed from the spec because its need was questionable. It may however be reintroduced in the future if there is enough demand from web developers.

IDBCursorSync 接口在 IndexedDB API represents a cursor for iterating over multiple records in a database. You can have only one instance of IDBCursorSync representing a cursor, but you can have an unlimited number of cursors at the same time. Operations are performed on the underlying index or object store. It enables an application to synchronously process all the records in the cursor's range.

方法概述

bool continue (in optional any key);

void remove () raises ( IDBDatabaseException );

属性

属性	类型	描述
count	readonly unsigned long long	The total number of objects that share the current key.
direction	readonly unsigned short	direction of traversal of the cursor. See Constants for possible values.
key	readonly any	The key for the record at the cursor's 位置 .
value	any	The value for the record at the cursor's position. Setting this attribute can raise an IDBDatabaseException with the following codes: DATA_ERR If the underlying object store uses in-line keys and the property at the key path does not match the key in this cursor's position. NOT_ALLOWED_ERR If the underlying index or object store does not support updating the record because it is open in the READ_ONLY or SNAPSHOT_READ mode, or if an index record cannot be changed because the underlying index is auto-populated . SERIAL_ERR If the data being stored could not be serialized by the internal structured cloning algorithm.

常量

常量	值	描述
NEXT	0	This cursor includes duplicates, and its direction is monotonically increasing in the order of keys.
NEXT_NO_DUPLICATE	1	This cursor does not include duplicates, and its direction is monotonically increasing in the order of keys.
PREV	2	This cursor includes duplicates, and its direction is monotonically decreasing in the order of keys.
PREV_NO_DUPLICATE	3	This cursor does not include duplicates, and its direction is monotonically decreasing in the order of keys.

方法

continue()

Advances the cursor to the next position along its direction, to the item whose key matches the optional key parameter. If no key is specified, advance to the immediate next position. Returns false if the cursor has reached the end of its range; otherwise returns true.

bool continue (
  in optional any key
);
				

参数

key

The key to which to move the cursor's position.

remove()

Deletes the record at the cursor's position, without changing the cursor's position

void delete (
) raises (DatabaseException);
					

异常

This method can raise an IDBDatabaseException with the following code:

NOT_ALLOWED_ERR

If the underlying index or object store does not support updating the record because it is open in the READ_ONLY or SNAPSHOT_READ 模式。

元数据

• 最后修改： 2019 年 3 月 23 日

相关话题

1. IndexedDB API
2. IDBCursorSync
3. 事件

   1. upgradeneeded
   2. complete
   3. abort
   4. success
   5. error
   6. blocked
   7. versionchange
   8. close
4. IndexedDB 相关页面

   1. IDBCursor
   2. IDBCursorWithValue
   3. IDBDatabase
   4. IDBDatabaseException
   5. IDBDatabaseSync
   6. IDBEnvironment
   7. IDBEnvironmentSync
   8. IDBFactory
   9. IDBFactorySync
   10. IDBIndex
   11. IDBIndexSync
   12. IDBKeyRange
   13. IDBObjectStore
   14. IDBObjectStoreSync
   15. IDBOpenDBRequest
   16. IDBRequest
   17. IDBTransaction
   18. IDBTransactionSync
   19. IDBVersionChangeEvent
   20. IDBVersionChangeRequest