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MutationRecord - Web APIs 编辑

A MutationRecord represents an individual DOM mutation. It is the object that is passed to MutationObserver's callback.

Properties

Property	Type	Description
`MutationRecord.type`	`String`	Returns `"attributes"` if the mutation was an attribute mutation, `"characterData"` if it was a mutation to a `CharacterData` node, and `"childList"` if it was a mutation to the tree of nodes.
`MutationRecord.target`	`Node`	Returns the node the mutation affected, depending on the `MutationRecord.type`. For `attributes`, it is the element whose attribute changed. For `characterData`, it is the `CharacterData` node. For `childList`, it is the node whose children changed.
`MutationRecord.addedNodes`	`NodeList`	Return the nodes added. Will be an empty `NodeList` if no nodes were added.
`MutationRecord.removedNodes`	`NodeList`	Return the nodes removed. Will be an empty `NodeList` if no nodes were removed.
`MutationRecord.previousSibling`	`Node`	Return the previous sibling of the added or removed nodes, or `null`.
`MutationRecord.nextSibling`	`Node`	Return the next sibling of the added or removed nodes, or `null`.
`MutationRecord.attributeName`	`String`	Returns the local name of the changed attribute, or `null`.
`MutationRecord.attributeNamespace`	`String`	Returns the namespace of the changed attribute, or `null`.
`MutationRecord.oldValue`	`String`	The return value depends on the `MutationRecord.type`. For `attributes`, it is the value of the changed attribute before the change. For `characterData`, it is the data of the changed node before the change. For `childList`, it is `null`. Note that for this to work as expected, `attributeOldValue` or `characterDataOldValue` must be set to `true` in the corresponding MutationObserverInit parameter of the `MutationObserver` observe method