MutationObserverInit.characterData

The MutationObserverInit dictionary's optional characterData property is used to specify whether or not to monitor the node or nodes being observed for changes to their textual contents.

Character data changes are detectable on any text node, including nodes based on the Text, ProcessingInstruction, and Comment interfaces.

Note that this doesn't monitor content of an HTMLElement, even if it only contains text inside, as it only monitors text nodes themselves. So either pass directly a text node to the observe() method or you need to also set subtree: true.

Syntax

var options = {
  characterData: true | false
}

Value

A Boolean value indicating whether or not to call the observer's callback function when textual nodes' values change.

If true, the callback specified when observe() was used to start observing the node or subtree is called any time the contents of a text node are changed.

You can expand the capabilities of attribute mutation monitoring using other options:

  • characterDataOldValue lets you specify whether or not you want the previous value of changed text nodes to be provided using the MutationRecord's oldValue property.
  • subtree lets you specify whether to watch the target node and all of its descendants (true), or just the target node (false).

If you set characterDataOldValue to true, characterData is automatically assumed to be true, even if you don't expressly set it as such.

Example

Specifications

Specification Status Comment
DOM
The definition of 'MutationObserverInit.characterData' in that specification.
Living Standard

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
characterDataChrome Full support 26
Full support 26
No support 18 — 26
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Edge Full support 12Firefox Full support 14
Notes
Full support 14
Notes
Notes Starting in Firefox 36, characterData has no default value; previously, its default value was false.
IE Full support 11Opera Full support 15Safari Full support 7
Full support 7
No support 6 — 7
Prefixed
Prefixed Implemented with the vendor prefix: webkit
WebView Android ? Chrome Android Full support 26
Full support 26
No support 18 — 26
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Firefox Android Full support 14
Notes
Full support 14
Notes
Notes Starting in Firefox 36, characterData has no default value; previously, its default value was false.
Opera Android Full support 14Safari iOS Full support 7
Full support 7
No support 6 — 7
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Samsung Internet Android Full support 1.5
Full support 1.5
No support 1.0 — 1.5
Prefixed
Prefixed Implemented with the vendor prefix: webkit

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.