Web Storage API support in Opera Presto 2.7

W3C reference

W3C Web Storage API

Web storage in Opera can be configured using preferences in the "Web Storage" section located in opera:config.

Opera supports the following web storage tools.

• Session storage: offers a temporary storage of data
• Local storage: stores data for a longer period until you explicitly clear it

Support has been added for the window.opera.scriptStorage property for user scripts alone. This property returns a Storage object as specified in the W3C Web Storage API Section 4.1: The Storage interface, and is unique per script.

• User scripts can use this object to share presistent data across web pages.
• Script storage objects currently do not fire storage events.
• The scriptStorage object has limited quota, defined in opera:config.

Opera does not currently support:

• Structured storage
• Storage mutex

Opera's support for the W3C Web Storage API is defined in the following data tables.

Interfaces

Interface	Attributes	Methods	Comment	Support
Storage	length	key(n) getItem(key) setItem(key, value) removeItem(key) clear()	This interface provides access to a list of key/value pairs, which are sometimes called items.	Yes
StorageEvent	key oldValue newValue url storageArea	initStorageEvent()	This interface event is fired when a storage area changes.	Yes

Attributes

Attribute	Comment	Support
sessionStorage	This attribute represents the set of storage areas specific to the current top-level browsing context.	Yes
localStorage	This attribute provides a Storage object for an origin. User agents must have a set of local storage areas, one for each origin.	Yes