<use> - SVG: Scalable Vector Graphics 编辑

The <use> element takes nodes from within the SVG document, and duplicates them somewhere else.

html,body,svg { height:100% }
<svg viewBox="0 0 30 10" xmlns="http://www.w3.org/2000/svg">
  <circle id="myCircle" cx="5" cy="5" r="4" stroke="blue"/>
  <use href="#myCircle" x="10" fill="blue"/>
  <use href="#myCircle" x="20" fill="white" stroke="red"/>
  <!--
stroke="red" will be ignored here, as stroke was already set on myCircle.
Most attributes (except for x, y, width, height and (xlink:)href)
do not override those set in the ancestor.
That's why the circles have different x positions, but the same stroke value.
  -->
</svg>

The effect is the same as if the nodes were deeply cloned into a non-exposed DOM, then pasted where the use element is, much like cloned template elements in HTML5.

Most attributes on use do not override those already on the element referenced by use. (This differs from how CSS style attributes override those set 'earlier' in the cascade). Only the attributes x, y, width, height and href on the use element will override those set on the referenced element. However, any other attributes not set on the referenced element will be applied to the use element.

Since the cloned nodes are not exposed, care must be taken when using CSS to style a use element and its cloned descendants. CSS properties are not guaranteed to be inherited by the cloned DOM unless you explicitly request them using CSS inheritance.

For security reasons, browsers may apply the same-origin policy on use elements and may refuse to load a cross-origin URL in the href attribute. There is currently no defined way to set a cross-origin policy for use elements.

Since SVG 2, the xlink:href attribute is deprecated in favor of href. See xlink:href page for more information. However, xlink:href can still be required in practice for cross-browser compatibility (see the compatibility table below).

Attributes

href
The URL to an element/fragment that needs to be duplicated.
Value type: <URL> ; Default value: none; Animatable: yes
xlink:href

Deprecated since SVG 2

This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

An <IRI> reference to an element/fragment that needs to be duplicated.
Value type: <IRI> ; Default value: none; Animatable: yes
x
The x coordinate of the use element.
Value type: <coordinate> ; Default value: 0; Animatable: yes
y
The y coordinate of the use element.
Value type: <coordinate> ; Default value: 0; Animatable: yes
width
The width of the use element.
Value type: <length> ; Default value: 0; Animatable: yes
height
The height of the use element.
Value type: <length> ; Default value: 0; Animatable: yes

Note: width, and height have no effect on use elements, unless the element referenced has a viewbox - i.e. they only have an effect when use refers to a svg or symbol element.

Note: Starting with SVG2, x, y, width, and height are Geometry Properties, meaning those attributes can also be used as CSS properties for that element.

Global attributes

Core Attributes
Most notably: id, tabindex
Styling Attributes
class, style
Conditional Processing Attributes
Most notably: requiredExtensions, systemLanguage
Event Attributes
Global event attributes, Graphical event attributes
Presentation Attributes
Most notably: clip-path, clip-rule, color, color-interpolation, color-rendering, cursor, display, fill, fill-opacity, fill-rule, filter, mask, opacity, pointer-events, shape-rendering, stroke, stroke-dasharray, stroke-dashoffset, stroke-linecap, stroke-linejoin, stroke-miterlimit, stroke-opacity, stroke-width, transform, vector-effect, visibility
ARIA Attributes
aria-activedescendant, aria-atomic, aria-autocomplete, aria-busy, aria-checked, aria-colcount, aria-colindex, aria-colspan, aria-controls, aria-current, aria-describedby, aria-details, aria-disabled, aria-dropeffect, aria-errormessage, aria-expanded, aria-flowto, aria-grabbed, aria-haspopup, aria-hidden, aria-invalid, aria-keyshortcuts, aria-label, aria-labelledby, aria-level, aria-live, aria-modal, aria-multiline, aria-multiselectable, aria-orientation, aria-owns, aria-placeholder, aria-posinset, aria-pressed, aria-readonly, aria-relevant, aria-required, aria-roledescription, aria-rowcount, aria-rowindex, aria-rowspan, aria-selected, aria-setsize, aria-sort, aria-valuemax, aria-valuemin, aria-valuenow, aria-valuetext, role
XLink Attributes
xlink:href, xlink:title

Usage notes

CategoriesGraphics element, Graphics referencing element, Structural element
Permitted contentAny number of the following elements, in any order:
Animation elements
Descriptive elements

Specifications

SpecificationStatusComment
Scalable Vector Graphics (SVG) 2
The definition of '<use>' in that specification.
Candidate Recommendation
Scalable Vector Graphics (SVG) 1.1 (Second Edition)
The definition of '<use>' in that specification.
RecommendationInitial definition

Browser compatibility

BCD tables only load in the browser

如果你对这篇内容有疑问,欢迎到本站社区发帖提问 参与讨论,获取更多帮助,或者扫码二维码加入 Web 技术交流群。

扫码二维码加入Web技术交流群

发布评论

需要 登录 才能够评论, 你可以免费 注册 一个本站的账号。
列表为空,暂无数据

词条统计

浏览:91 次

字数:13864

最后编辑:7 年前

编辑次数:0 次

    我们使用 Cookies 和其他技术来定制您的体验包括您的登录状态等。通过阅读我们的 隐私政策 了解更多相关信息。 单击 接受 或继续使用网站,即表示您同意使用 Cookies 和您的相关数据。
    原文