Element

Element 介面表示了一個在 Document 中的物件，其描述了各類型元素的共同屬性與方法，Element 的子介面則定義了不同類型元素的具體行為並增加額外的功能。例如 HTMLElement 為所有 HTML 元素的基礎介面，而 SVGElement 則是定義所有 SVG 元素的介面。

在 Web 領域之外，如 XUL 語言也能藉由 XULElement 介面來繼承 Element。

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  a:hover text { fill: #0095DD; pointer-events: all;}

屬性

Inherits properties from its parent interface, Node, and by extension that interface's parent, EventTarget. It implements the properties of ParentNode, ChildNode, NonDocumentTypeChildNode, and Animatable.

Element.assignedSlot Read only

Returns the HTMLSlotElement interface associated with the element.

Element.attributes Read only

Returns a NamedNodeMap object containing the assigned attributes of the corresponding HTML element.

Element.classList Read only

Returns a DOMTokenList containing the list of class attributes.

Element.className

Is a DOMString representing the class of the element.

Element.clientHeight Read only

Returns a Number representing the inner height of the element.

Element.clientLeft Read only

Returns a Number representing the width of the left border of the element.

Element.clientTop Read only

Returns a Number representing the width of the top border of the element.

Element.clientWidth Read only

Returns a Number representing the inner width of the element.

Element.computedName Read only

Returns a DOMString containing the label exposed to accessibility.

Element.computedRole Read only

Returns a DOMString containing the ARIA role that has been applied to a particular element.

Element.id

Is a DOMString representing the id of the element.

Element.innerHTML

Is a DOMString representing the markup of the element's content.

Element.localName Read only

A DOMString representing the local part of the qualified name of the element.

Element.namespaceURI Read only

The namespace URI of the element, or null if it is no namespace.

Note: In Firefox 3.5 and earlier, HTML elements are in no namespace. In later versions, HTML elements are in the http://www.w3.org/1999/xhtml namespace in both HTML and XML trees.

NonDocumentTypeChildNode.nextElementSibling Read only

Is a Element, the element immediately following the given one in the tree, or null if there's no sibling node.

Element.outerHTML

Is a DOMString representing the markup of the element including its content. When used as a setter, replaces the element with nodes parsed from the given string.

Element.prefix Read only

A DOMString representing the namespace prefix of the element, or null if no prefix is specified.

NonDocumentTypeChildNode.previousElementSibling Read only

Is a Element, the element immediately preceding the given one in the tree, or null if there is no sibling element.

Element.scrollHeight Read only

Returns a Number representing the scroll view height of an element.

Element.scrollLeft

Is a Number representing the left scroll offset of the element.

Element.scrollLeftMax Read only

Returns a Number representing the maximum left scroll offset possible for the element.

Element.scrollTop

Is a Number representing the top scroll offset the an element.

Element.scrollTopMax Read only

Returns a Number representing the maximum top scroll offset possible for the element.

Element.scrollWidth Read only

Returns a Number representing the scroll view width of the element.

Element.shadowRoot Read only

Returns the youngest shadow root that is hosted by the element.

Element.slot

Returns the name of the shadow DOM slot attatched to the element. A slot is a placeholder inside a web component that users can fill with their own markup.

Element.tabStop

Is a Boolean indicating if the element can receive input focus via the tab key.

Element.tagName Read only

Returns a String with the name of the tag for the given element.

Element.undoManager Read only

Returns the UndoManager associated with the element.

Element.undoScope

Is a Boolean indicating if the element is an undo scope host, or not.

事件處理器

Element.ongotpointercapture

Returns the event handler for the gotpointercapture event type.

Element.onlostpointercapture

Returns the event handler for the lostpointercapture event type.

Element.onwheel

Returns the event handling code for the wheel event.

方法

Inherits methods from its parents Node, and its own parent, EventTarget, and implements those of ParentNode, ChildNode, NonDocumentTypeChildNode, and Animatable.

EventTarget.addEventListener()

Registers an event handler to a specific event type on the element.

Element.attachShadow()

Attatches a shadow DOM tree to the specified element and returns a reference to its ShadowRoot.

Element.animate()

A shortcut method to create and run an animation on an element. Returns the created Animation object instance.

Element.closest()

Returns the Element, descendant of this element (or this element itself), that is the closest ancestor of the elements selected by the selectors given in parameter.

Element.createShadowRoot()

Creates a shadow DOM on on the element, turning it into a shadow host. Returns a ShadowRoot.

EventTarget.dispatchEvent()

Dispatches an event to this node in the DOM and returns a Boolean that indicates that at least one handler has not canceled it.

Element.find()

...

Element.findAll()

...

Element.getAnimations()

Returns an array of Animation objects currently active on the element.

Element.getAttribute()

Retrieves the value of the named attribute from the current node and returns it as an Object.

Element.getAttributeNames()

 

Element.getAttributeNS()

Retrieves the value of the attribute with the specified name and namespace, from the current node and returns it as an Object.

Element.getAttributeNode()

Retrieves the node representation of the named attribute from the current node and returns it as an Attr.

Element.getAttributeNodeNS()

Retrieves the node representation of the attribute with the specified name and namespace, from the current node and returns it as an Attr.

Element.getBoundingClientRect()

...

Element.getClientRects()

Returns a collection of rectangles that indicate the bounding rectangles for each line of text in a client.

Element.getDestinationInsertionPoints()

…

Element.getElementsByClassName()

Returns a live HTMLCollection that contains all descendants of the current element that possess the list of classes given in the parameter.

Element.getElementsByTagName()

Returns a live HTMLCollection containing all descendant elements, of a particular tag name, from the current element.

Element.getElementsByTagNameNS()

Returns a live HTMLCollection containing all descendant elements, of a particular tag name and namespace, from the current element.

Element.hasAttribute()

Returns a Boolean indicating if the element has the specified attribute or not.

Element.hasAttributeNS()

Returns a Boolean indicating if the element has the specified attribute, in the specified namespace, or not.

Element.hasAttributes()

Returns a Boolean indicating if the element has one or more HTML attributes present.

Element.insertAdjacentElement

Inserts a given element node at a given position relative to the element it is invoked upon.

Element.insertAdjacentHTML

Parses the text as HTML or XML and inserts the resulting nodes into the tree in the position given.

Element.insertAdjacentText

Inserts a given text node at a given position relative to the element it is invoked upon.

Element.matches()

Returns a Boolean indicating whether or not the element would be selected by the specified selector string.

Element.querySelector()

Returns the first Node which matches the specified selector string relative to the element.

Element.querySelectorAll

Returns a NodeList of nodes which match the specified selector string relative to the element.

Element.releasePointerCapture

Releases (stops) pointer capture that was previously set for a specific pointer event.

ChildNode.remove()

Removes the element from the children list of its parent.

Element.removeAttribute()

Removes the named attribute from the current node.

Element.removeAttributeNS()

Removes the attribute with the specified name and namespace, from the current node.

Element.removeAttributeNode()

Removes the node representation of the named attribute from the current node.

EventTarget.removeEventListener()

Removes an event listener from the element.

Element.requestFullscreen()

Asynchronously asks the browser to make the element full-screen.

Element.requestPointerLock()

Allows to asynchronously ask for the pointer to be locked on the given element.

Element.scrollIntoView()

Scrolls the page until the element gets into the view.

Element.setAttribute()

Sets the value of a named attribute of the current node.

Element.setAttributeNS()

Sets the value of the attribute with the specified name and namespace, from the current node.

Element.setAttributeNode()

Sets the node representation of the named attribute from the current node.

Element.setAttributeNodeNS()

Setw the node representation of the attribute with the specified name and namespace, from the current node.

Element.setCapture()

Sets up mouse event capture, redirecting all mouse events to this element.

Element.setPointerCapture()

Designates a specific element as the capture target of future pointer events.

規範

瀏覽器相容性

[1] Internet Explorer 7 and 8 incorrectly return the comments as part of the children of an Element. This is fixed in Internet Explorer 9 and later.

[2] Chrome 16 allowed webkitRequestPointerLock() only in fullscreen; Chrome 21 for trusted web site (permission asked); Chrome 22 allowed it by default for all same-origin document; Chrome 23 allowed it in sandboxed <iframe> if the non-standard value webkit-allow-pointer-lock is set to the sandbox attribute.

[3] Implementation withdrawn. See bug 1166347.

[4] Behind a flag.