UserDataHandler - Web APIs 编辑

Obsolete since Gecko 26 (Firefox 26 / Thunderbird 26 / SeaMonkey 2.23 / Firefox OS 1.2)

This feature is obsolete.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.

Summary

When associating user data with a key on a node, Node.setUserData() can also accept, in its third argument, a handler which will be called when the object is cloned, imported, deleted, renamed, or adopted. Per the specification, exceptions should not be thrown in a UserDataHandler. In both document.importNode() and Node.cloneNode(), although user data is not copied over, the handler will be called.

Properties

None.

Methods

handle (operation, key, data, src, dst) (no return value)

This method is a callback which will be called if a node is being cloned, imported, renamed and as well, if deleted or adopted.

• operation (unsigned short) is an operation type integer (see below).
• key (DOMString) is the user key.
• data (DOMUserData) is the user data.
• src (Node) is the source node (null if being deleted).
• dst (Node) is the destination node (if any, or null).

Constants

(NODE_RENAMED is currently not supported since Node.renameNode() is not supported.)

Specifications

DOM Level 3 Core: UserDataHandler

Browser compatibility

BCD tables only load in the browser

See also

• DOMUserData
• Node.getUserData, Node.setUserData