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MutationEvent: initMutationEvent() method

Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

Non-standard: This feature is not standardized. We do not recommend using non-standard features in production, as they have limited browser support, and may change or be removed. However, they can be a suitable alternative in specific cases where no standard option exists.

The initMutationEvent() method of the MutationEvent interface initializes the value of a mutation event once it's been created (normally using the Document.createEvent() method).

This method must be called to set the event before it is dispatched, using EventTarget.dispatchEvent().

Note: In general, you won't create these events yourself; they are created by the browser.

Syntax

initMutationEvent(type, canBubble, cancelable, relatedNode,
                  prevValue, newValue, attrName, attrChange)

Parameters

type: A string to set the event's type to. Browsers set the following values for MutationEvent: DOMAttrModified, DOMAttributeNameChanged, DOMCharacterDataModified, DOMElementNameChanged, DOMNodeInserted, DOMNodeInsertedIntoDocument, DOMNodeRemoved, DOMNodeRemovedFromDocument, DOMSubtreeModified.
canBubble: A boolean indicating whether or not the event can bubble. Sets the value of Event.bubbles.
cancelable: A boolean indicating whether or not the event's default action can be prevented. Sets the value of Event.cancelable.
relatedNode: A string representing the new value of the modified node, if any. Sets the value of MutationEvent.relatedNode.
prevValue: A string representing the previous value of the modified node, if any. Sets the value of MutationEvent.prevValue.
newValue: A string representing the new value of the modified node, if any. Sets the value of MutationEvent.newValue.
attrName: A string representing the name of the Attr node changed, if any. Sets the value of MutationEvent.attrName.
attrChange: A integer representing the reason attribute node changed. Sets the value of MutationEvent.attrChange.

Return value

None (undefined).

Specifications

This feature does not appear to be defined in any specification.>

Browser compatibility

	Desktop					Mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS
`initMutationEvent`	1–127	12–127	1–140	≤12.1	1–26	18–127	4–140	≤12.1	1–26	1.0–28.0	4.4–127	1–26

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https://developer.mozilla.org/en-US/docs/Web/API/MutationEvent/initMutationEvent