<symbol> - SVG: Scalable Vector Graphics 编辑

The <symbol> element is used to define graphical template objects which can be instantiated by a <use> element.

The use of symbol elements for graphics that are used multiple times in the same document adds structure and semantics. Documents that are rich in structure may be rendered graphically, as speech, or as Braille, and thus promote accessibility.

html,body,svg { height:100% }

<svg viewBox="0 0 80 20" xmlns="http://www.w3.org/2000/svg"
     xmlns:xlink="http://www.w3.org/1999/xlink">
  <!-- Our symbol in its own coordinate system -->
  <symbol id="myDot" width="10" height="10" viewBox="0 0 2 2">
    <circle cx="1" cy="1" r="1" />
  </symbol>

   <!-- A grid to materialize our symbol positioning -->
  <path d="M0,10 h80 M10,0 v20 M25,0 v20 M40,0 v20 M55,0 v20 M70,0 v20" fill="none" stroke="pink" />

  <!-- All instances of our symbol -->
  <use xlink:href="#myDot" x="5"  y="5" style="opacity:1.0" />
  <use xlink:href="#myDot" x="20" y="5" style="opacity:0.8" />
  <use xlink:href="#myDot" x="35" y="5" style="opacity:0.6" />
  <use xlink:href="#myDot" x="50" y="5" style="opacity:0.4" />
  <use xlink:href="#myDot" x="65" y="5" style="opacity:0.2" />
</svg>

Attributes

height

This attribute determines the height of the symbol.
Value type: <length>|<percentage> ; Default value: auto; Animatable: yes

preserveAspectRatio

This attribute defines how the svg fragment must be deformed if it is embedded in a container with a different aspect ratio.
Value type: (none| xMinYMin| xMidYMin| xMaxYMin| xMinYMid| xMidYMid| xMaxYMid| xMinYMax| xMidYMax| xMaxYMax) (meet|slice)? ; Default value: xMidYMid meet; Animatable: yes

refX

This attribute determines the x coordinate of the reference point of the symbol.
Value type: <length>|<percentage>|left|center|right ; Default value: 0; Animatable: yes

refY

This attribute determines the y coordinate of the reference point of the symbol.
Value type: <length>|<percentage>|top|center|bottom ; Default value: 0; Animatable: yes

viewBox

This attribute defines the bound of the SVG viewport for the current symbol.
Value type: <list-of-numbers> ; Default value: none; Animatable: yes

width

This attribute determines the width of the symbol.
Value type: <length>|<percentage> ; Default value: auto; Animatable: yes

x

This attribute determines the x coordinate of the symbol.
Value type: <length>|<percentage> ; Default value: 0; Animatable: yes

y

This attribute determines the y coordinate of the symbol.
Value type: <length>|<percentage> ; Default value: 0; Animatable: yes

Global attributes

Core Attributes

Most notably: id

Styling Attributes

class, style

Event Attributes

Global event attributes, Document element 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

Usage notes

Note: A <symbol> element itself is not meant to be rendered. Only instances of a <symbol> element (i.e., a reference to a <symbol> by a <use> element) are rendered. That means that some browsers could refuse to directly display a <symbol> element even if the CSS display property tells otherwise.

Specifications

Browser compatibility

BCD tables only load in the browser