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| author | MDN <actions@users.noreply.github.com> | 2022-03-19 00:13:08 +0000 |
|---|---|---|
| committer | MDN <actions@users.noreply.github.com> | 2022-03-19 00:13:08 +0000 |
| commit | 9bf6693b2edd5281c1577856895c55653a41dc01 (patch) | |
| tree | 0143e1d1d5c95776e42d8d9afdddedb13a0827c1 /files/zh-cn/web/css/env() | |
| parent | 376471eb81e0a3dc263128f834e3c8c22bb9b4d6 (diff) | |
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[CRON] sync translated content
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| -rw-r--r-- | files/zh-cn/web/css/env()/index.html | 133 |
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diff --git a/files/zh-cn/web/css/env()/index.html b/files/zh-cn/web/css/env()/index.html deleted file mode 100644 index 60f45d0e97..0000000000 --- a/files/zh-cn/web/css/env()/index.html +++ /dev/null @@ -1,133 +0,0 @@ ---- -title: env() -slug: Web/CSS/env() -tags: - - CSS - - env - - env() - - iPhoneX -translation_of: Web/CSS/env() ---- -<div>{{CSSRef}}</div> - -<div> <span class="seoSummary"><strong><code>env()</code></strong> <a href="/en-US/docs/Web/CSS">CSS</a> </span>函数以类似于 <span class="seoSummary">{{cssxref("var")}} </span>函数和 <span class="seoSummary"><a href="/en-US/docs/Web/CSS/--*">custom properties</a> </span>的方式将用户代理定义的环境变量值插入你的 CSS 中。区别在于,环境变量除了由用户代理定义而不是由用户定义外,还被全局作用在文档中,而自定义属性则限定在声明它们的元素中。</div> - - - -<div><span style="font-size: 1rem; letter-spacing: -0.00278rem;">为了告诉浏览器使用屏幕上所有的可用空间,并以此使用</span><code style="font-size: 1rem; letter-spacing: -0.00278rem;">env()</code><span style="font-size: 1rem; letter-spacing: -0.00278rem;">变量,我们需要添加一个新的视</span><span style="font-size: 1rem; letter-spacing: -0.00278rem;">口元值:</span></div> - -<div class="highlight highlight-text-html-basic"> -<pre><<span class="pl-ent">meta</span> <span class="pl-e">name</span>=<span class="pl-s"><span class="pl-pds">"</span>viewport<span class="pl-pds">"</span></span> <span class="pl-e">content</span>=<span class="pl-s"><span class="pl-pds">"</span>... <strong>viewport-fit=cover</strong><span class="pl-pds">"</span></span>></pre> -</div> - -<pre class="brush: css">body { - padding: - env(safe-area-inset-top, 20px) - env(safe-area-inset-right, 20px) - env(safe-area-inset-bottom, 20px) - env(safe-area-inset-left, 20px); -}</pre> - -<p>另外,与自定义属性不同,自定义属性不能在声明之外使用,而<code>env()</code>函数可以代替属性值或描述符的任何部分(例如,在 <a href="/en-US/docs/Web/CSS/@media">媒体查询的规则</a> 中)。 随着规范的发展,它也可能在像是 选择器 等其他地方使用。</p> - -<p>最初由iOS浏览器提供,用于允许开发人员将其内容放置在视口的安全区域中,该规范中定义的<code>safe-area-inset-* </code>值可用于确保内容即使在非矩形的视区中也可以完全显示。</p> - -<h2 id="语法">语法</h2> - -<pre class="brush: css">/* Using the four safe area inset values with no fallback values */ -env(safe-area-inset-top); -env(safe-area-inset-right); -env(safe-area-inset-bottom); -env(safe-area-inset-left); - -/* Using them with fallback values */ -env(safe-area-inset-top, 20px); -env(safe-area-inset-right, 1em); -env(safe-area-inset-bottom, 0.5vh); -env(safe-area-inset-left, 1.4rem); -</pre> - -<h3 id="Values">Values</h3> - -<dl> - <dt><code id="safe-area-inset-top" style="white-space: nowrap;">safe-area-inset-top</code>, <code id="safe-area-inset-right" style="white-space: nowrap;">safe-area-inset-right</code>, <code id="safe-area-inset-bottom" style="white-space: nowrap;">safe-area-inset-bottom</code>, <code id="safe-area-inset-left" style="white-space: nowrap;">safe-area-inset-left</code></dt> - <dd><code style="white-space: nowrap;">safe-area-inset-*</code>由四个定义了视口边缘内矩形的 top, right, bottom 和 left 的环境变量组成,这样可以安全地放入内容,而不会有被非矩形的显示切断的风险。对于矩形视口,例如普通的笔记本电脑显示器,其值等于零。 对于非矩形显示器(如圆形表盘,iPhoneX屏幕),在用户代理设置的四个值形成的矩形内,所有内容均可见。</dd> -</dl> - -<p><strong>注意</strong>: 不同于其他的 CSS 属性,用户代理定义的属性名字对大小写敏感。</p> - -<h3 id="Formal_syntax">Formal syntax</h3> - -{{CSSSyntax}} - -<h2 id="Examples">Examples</h2> - -<p>下面的示例使用<code>env()</code>的第二个可选参数,如果环境变量不可用,该参数可让您设置备用值</p> - -<pre class="brush: html"><p> - If the <code>env()</code> function is supported in your browser, - this paragraph’s text will have 50px of padding between it and - the left border — but not the top, right and bottom. - This is because the accompanying CSS is the equivalent of - <code>padding: 0 0 0 50px</code>, because, unlike other CSS - properties, user agent property names are case-sensitive. -</p></pre> - -<pre class="brush: css">p { - width: 300px; - border: 2px solid red; - padding: - env(safe-area-inset-top, 50px) - env(safe-area-inset-right, 50px) - env(safe-area-inset-bottom, 50px) - env(SAFE-AREA-INSET-LEFT, 50px); -}</pre> - -<p>{{EmbedLiveSample("Examples")}}</p> - -<h3 id="Example_values">Example values</h3> - -<pre class="brush: css">padding: env(safe-area-inset-bottom, 50px); /* zero for all rectangular user agents */ -padding: env(Safe-area-inset-bottom, 50px); /* 50px because UA properties are case sensitive */ -padding: env(x, 50px 20px); /* as if padding: '50px 20px' were set because x is not a valid environment variable */ -padding: env(x, 50px, 20px); /* ignored because '50px, 20px' is not a valid padding value and x is not a valid environment variable */ -</pre> - -<p>向下兼容的语法和自定义属性一样,允许使用逗号。但是如果属性值不支持逗号,则该值无效。</p> - -<p><strong>Note</strong>: User agent properties are not reset by the <a href="/en-US/docs/Web/CSS/all">all</a> property.</p> - -<h2 id="Specifications">Specifications</h2> - -<table class="standard-table"> - <thead> - <tr> - <th scope="col">Specification</th> - <th scope="col">Status</th> - <th scope="col">Comment</th> - </tr> - </thead> - <tbody> - <tr> - <td>{{SpecName("CSS3 Environment Variables", "#env-function", "env()")}}</td> - <td>{{Spec2("CSS3 Environment Variables")}}</td> - <td>Initial definition.</td> - </tr> - </tbody> -</table> - -<h2 id="Browser_compatibility">Browser compatibility</h2> - - - -<p>{{Compat("css.properties.custom-property.env")}}</p> - -<h2 id="See_also">See also</h2> - -<ul> - <li>{{CSSxRef("var", "var(…)")}}</li> - <li><a href="/en-US/docs/Web/CSS/CSS_Variables">CSS Custom Properties for Cascading Variables</a></li> - <li><a href="/en-US/docs/Web/CSS/--*">Custom Properties (--*)</a></li> - <li><a href="/en-US/docs/Web/CSS/Using_CSS_variables">Using CSS custom properties (variables)</a></li> - <li>{{CSSxRef("@viewport/viewport-fit", "viewport-fit (@viewport)")}}</li> -</ul> |
