CustomElementRegistry
Baseline
Widely available
*
This feature is well established and works across many devices and browser versions. It’s been available across browsers since January 2020.
* Some parts of this feature may have varying levels of support.
The CustomElementRegistry interface provides methods for registering custom elements and querying registered elements. To get an instance of it, use the window.customElements property. To create a scoped registry, use the CustomElementRegistry() constructor.
Constructor
CustomElementRegistry()-
Creates a new
CustomElementRegistryobject, for scoped usage.
Instance methods
CustomElementRegistry.define()-
Defines a new custom element.
CustomElementRegistry.get()-
Returns the constructor for the named custom element, or
undefinedif the custom element is not defined. CustomElementRegistry.getName()-
Returns the name for the already-defined custom element, or
nullif the custom element is not defined. CustomElementRegistry.upgrade()-
Upgrades a custom element directly, even before it is connected to its shadow root.
CustomElementRegistry.initialize()-
Associates a scoped registry with a DOM subtree, setting the custom element registry on each inclusive descendant and upgrading any custom elements.
CustomElementRegistry.whenDefined()-
Returns an empty
Promisethat resolves when a custom element becomes defined with the given name. If such a custom element is already defined, the returned promise is immediately fulfilled.
Examples
See the Examples section in our guide to using custom elements.
Specifications
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Browser compatibility
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CustomElementRegistry
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CustomElementRegistry() constructor
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define
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connectedMoveCallback() lifecycle callback
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Supports
disabledFeatures static property
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Emoji and more Unicode in element and attribute names and namespace prefix (valid names match HTML parser)
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get
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getName
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initialize
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upgrade
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whenDefined
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Legend
Tip: you can click/tap on a cell for more information.
- Full support
- Full support
- Partial support
- Partial support
- No support
- No support
- See implementation notes.