MutationEvent: prevValue property

{{APIRef("UI Events")}}{{Deprecated_Header}}{{non-standard_header}}

The prevValue read-only property of the {{domxref("MutationEvent")}} interface returns a string. In DOMAttrModified events, it represents the previous value of the {{domxref("Attr")}} node. In DOMCharacterDataModified events, it contains the previous value of the {{domxref("CharacterData")}} node. In all other cases, returns the empty string ("").

Value

A string.

Examples

element.addEventListener("DOMAttrModified", (event) => {
  console.log(event.previousValue);
});

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}