range - CSS: Cascading Style Sheets 编辑

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.

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.

Description

The 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.

Formal definition

Related at-rule@counter-style
Initial valueauto
Computed valueas specified

Formal syntax

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

Examples

Setting counter style over a range

<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

SpecificationStatusComment
CSS Counter Styles Level 3
The definition of 'range' in that specification.
Candidate RecommendationInitial definition

Browser compatibility

BCD tables only load in the browser

See also

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:89 次

字数:7603

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