UserDataHandler

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This feature is obsolete.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

Constant Value Operation
NODE_CLONED 1 Node.cloneNode()
NODE_IMPORTED 2 Document.importNode()
NODE_DELETED Unimplemented (see bug 550400) 3  
NODE_RENAMED Unimplemented 4 Node.renameNode()
NODE_ADOPTED 5 Document.adoptNode()

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

Specification

DOM Level 3 Core: UserDataHandler

See also

License

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/userdatahandler

API DOM NeedsMarkupWork Obsolete