HTML - <content>

Example

Here is a simple example of using the <content> element. It is an HTML file with everything needed in it.

Note: For this code to work, the browser you display it in must support Web Components. See Enabling Web Components in Firefox.

HTML

Copy Code

<html>
  <head></head>
  <body>
  <!-- The original content accessed by <content> -->
  <div>
    <h4>My Content Heading</h4>
    <p>My content text</p>
  </div>

  <script>
  // Get the <div> above.
  var myContent = document.querySelector('div');
  // Create a shadow DOM on the <div>
  var shadowroot = myContent.createShadowRoot();
  // Insert into the shadow DOM a new heading and 
  // part of the original content: the <p> tag.
  shadowroot.innerHTML =
   '<h2>Inserted Heading</h2> <content select="p"></content>';
  </script>

  </body>
</html>

If you display this in a web browser it should look like the following.

content example

Description

Deprecated
This feature has been removed from the Web standards. Though some browsers may still support it, it is in the process of being dropped. Do not use it in old or new projects. Pages or Web apps using it may break at any time.

The HTML <content> element is used inside of Shadow DOM as an insertion point. It is not intended to be used in ordinary HTML. It is used with Web Components. It has now been replaced by the <slot> element.

Note: Though present in early draft of the specifications and implemented in several browsers, this element has been removed in later versions of the spec.

Content categories	Transparent content.
Permitted content	Flow content.
Tag omission	None, both the starting and ending tag are mandatory.
Permitted parent elements	Any element that accepts flow content.
DOM interface	`HTMLContentElement`

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari (WebKit)
Basic support	35	28 (28) [1]	No support	26	No support

Feature	Android	Firefox Mobile (Gecko)	IE Phone	Opera Mobile	Safari Mobile
Basic support	37	28.0 (28) [1]	No support	?	?

[1] If Shadow DOM is not enabled in Firefox, <content> elements will behave like HTMLUnknownElement. Shadow DOM was first implemented in Firefox 33 and is behind a preference, dom.webcomponents.enabled, which is disabled by default.

Specifications

Specification	Status	Comment
Shadow DOM The definition of 'content' in that specification.	Working Draft

License

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/html/element/content

Deprecated Element HTML NeedsContent Reference Web Web Components web components