Please note, this is a STATIC archive of website developer.mozilla.org from 03 Nov 2016, cach3.com does not collect or store any user information, there is no "phishing" involved.

range

这篇文章需要技术复核。如何帮忙。

我们的志愿者还没有将这篇文章翻译为 中文 (简体)加入我们帮助完成翻译!

Summary

When defining custom counter styles, the range descriptor lets the author specify a range of counter values over which the style is applied. If a counter value is outside the specified range, then the fallback style will be used to construct the representation of that marker. Value of the range descriptor can be either auto or a comma separated list of lower and upper bounds specified as integers.

If value is auto, then for cyclic, numeric, and fixed system, the range will be from negative infinity to positive infinity. For alphabetic and symbolic systems, range will be from 1 to positive infinity. For additive systems, auto will result in the range 0 to positive infinity. For extends systems, the range is whatever auto will produce for the extended system.

When range is specified as integers, the value 'infinite' can be used to denote infinity. If infinite is specified as the first value in a range, then it is interpreted as negative infinity. If used as upper bound, it is taken as positive infinity.

Related at-rule@counter-style
Initial valueauto
Mediaall
Computed valueas specified
Canonical orderorder of appearance in the formal grammar of the values

Syntax

/* Keyword value */
range: auto;

/* Range values */
range: 2 5;
range: infinite 10;
range: 6 infinite;
range: infinite infinite;

/* Multiple range values */
range: 2 5, 8 10;
range: infinite 6, 10 infinite;

Values

auto
The range depends on the counter system:
  • For cyclic, numeric, and fixed systems, the range is negative infinity to positive infinity.
  • For alphabetic and symbolic systems, the range is 1 to positive infinity.
  • For additive systems, the range is 0 to positive infinity.
  • For extends systems, the range is whatever auto would produce for the extended system; if extending a complex predefined style (§7 Complex Predefined Counter Styles), the range is the style’s defined range.
[ [ | infinite ]{2} ]#
Defines a comma-separated list of ranges. For each individual range, the first value is the lower bound and the second value is the upper bound. A range is inclusive, that means it always contains both, the lower and upper bound numbers. If infinite is used as the first value in a range, it represents negative infinity; if it is used as the second value, it represents positive infinity. The range of the counter style is the union of all the ranges defined in the list.
If the lower bound of any range is higher than the upper bound, the entire descriptor is invalid and will be ignored.

Formal syntax

[ [ <integer> | infinite ]{2} ]# | auto

Example

<ul class="list">
  <li>One</li>
  <li>Two</li>
  <li>Three</li>
  <li>Four</li>
  <li>Five</li>
  <li>Six</li>
  <li>Seven</li>
  <li>Eight</li>
  <li>Nine</li>
  <li>Ten</li>
</ul>
@counter-style range-multi-example {
  system: cyclic;
  symbols: "\25A0" "\25A1";
  range: 2 4, 7 9;
}

.list {
  list-style: range-multi-example;    
}

The above list will display as follows:

   1. One
  □. Two
  ■. Three
  □. Four
   5. Five
   6. Six
  ■. Seven
  □. Eight
  ■. Nine
  10. Ten

Specifications

Specification Status Comment
CSS Counter Styles Level 3
The definition of 'range' in that specification.
Candidate Recommendation Initial definition

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support No support 33 (33) No support No support No support
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support 33 (33) No support No support No support

See also

文档标签和贡献者

 此页面的贡献者: Sebastianz, kscarfone, jsx
 最后编辑者: Sebastianz,