The MutationObserverInit
dictionary describes the configuration of a mutation observer. As such, it's primarily used as the type of the options
parameter on the MutationObserver.observe()
method.
Properties
At a minimum, one of childList
, attributes
, and/or characterData
must be true
when you call observe()
. Otherwise, a TypeError
exception will be thrown.
subtree
Optional- Set to
true
to extend monitoring to the entire subtree of nodes rooted attarget
. All of the otherMutationObserverInit
properties are then extended to all of the nodes in the subtree instead of applying solely to thetarget
node. The default value isfalse
. childList
Optional- Set to
true
to monitor the target node (and, ifsubtree
istrue
, its descendants) for the addition of new child nodes or removal of existing child nodes. The default value isfalse
. attributes
Optional- Set to
true
to watch for changes to the value of attributes on the node or nodes being monitored. The default value istrue
if either ofattributeFilter
orattributeOldValue
is specified, otherwise the default value isfalse
. attributeFilter
Optional- An array of specific attribute names to be monitored. If this property isn't included, changes to all attributes cause mutation notifications.
attributeOldValue
Optional- Set to
true
to record the previous value of any attribute that changes when monitoring the node or nodes for attribute changes; see Monitoring attribute values in MutationObserver for details on watching for attribute changes and value recording. The default value isfalse
. characterData
Optional- Set to
true
to monitor the specified target node (and, ifsubtree
istrue
, its descendants) for changes to the character data contained within the node or nodes. The default value istrue
ifcharacterDataOldValue
is specified, otherwise the default value isfalse
. characterDataOldValue
Optional- Set to
true
to record the previous value of a node's text whenever the text changes on nodes being monitored. For details and an example, see Monitoring text content changes in MutationObserver. The default value isfalse
.
Specifications
Specification | Status | Comment |
---|---|---|
DOM The definition of 'MutationObserverInit' in that specification. |
Living Standard |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
MutationObserverInit | Chrome
Full support
26
| Edge Full support 12 | Firefox Full support 14 | IE Full support 11 | Opera Full support 15 | Safari
Full support
7
| WebView Android ? | Chrome Android
Full support
26
| Firefox Android Full support 14 | Opera Android Full support 14 | Safari iOS
Full support
7
| Samsung Internet Android
Full support
1.5
|
attributeFilter | Chrome
Full support
26
| Edge
Full support
12
| Firefox Full support 14 | IE
Full support
11
| Opera Full support 15 | Safari
Full support
7
| WebView Android ? | Chrome Android
Full support
26
| Firefox Android Full support 14 | Opera Android Full support 14 | Safari iOS
Full support
7
| Samsung Internet Android
Full support
1.5
|
attributeOldValue | Chrome
Full support
26
| Edge Full support 12 | Firefox
Full support
14
| IE Full support 11 | Opera Full support 15 | Safari
Full support
7
| WebView Android ? | Chrome Android
Full support
26
| Firefox Android
Full support
14
| Opera Android Full support 14 | Safari iOS
Full support
7
| Samsung Internet Android
Full support
1.5
|
attributes | Chrome
Full support
26
| Edge Full support 12 | Firefox
Full support
14
| IE Full support 11 | Opera Full support 15 | Safari
Full support
7
| WebView Android ? | Chrome Android
Full support
26
| Firefox Android
Full support
14
| Opera Android Full support 14 | Safari iOS
Full support
7
| Samsung Internet Android
Full support
1.5
|
characterData | Chrome
Full support
26
| Edge Full support 12 | Firefox
Full support
14
| IE Full support 11 | Opera Full support 15 | Safari
Full support
7
| WebView Android ? | Chrome Android
Full support
26
| Firefox Android
Full support
14
| Opera Android Full support 14 | Safari iOS
Full support
7
| Samsung Internet Android
Full support
1.5
|
characterDataOldValue | Chrome
Full support
26
| Edge Full support 12 | Firefox
Full support
14
| IE Full support 11 | Opera Full support 15 | Safari
Full support
7
| WebView Android ? | Chrome Android
Full support
26
| Firefox Android
Full support
14
| Opera Android Full support 14 | Safari iOS
Full support
7
| Samsung Internet Android
Full support
1.5
|
childList | Chrome
Full support
26
| Edge Full support 12 | Firefox Full support 14 | IE Full support 11 | Opera Full support 15 | Safari
Full support
7
| WebView Android ? | Chrome Android
Full support
26
| Firefox Android Full support 14 | Opera Android Full support 14 | Safari iOS
Full support
7
| Samsung Internet Android
Full support
1.5
|
subtree | Chrome
Full support
26
| Edge Full support 12 | Firefox Full support 14 | IE Full support 11 | Opera Full support 15 | Safari
Full support
7
| WebView Android ? | Chrome Android
Full support
26
| Firefox Android Full support 14 | Opera Android Full support 14 | Safari iOS
Full support
7
| Samsung Internet Android
Full support
1.5
|
Legend
- Full support
- Full support
- Compatibility unknown
- Compatibility unknown
- See implementation notes.
- See implementation notes.
- Requires a vendor prefix or different name for use.
- Requires a vendor prefix or different name for use.