关于css:是否可以使用SVG作为伪元素中的内容:before或:after

Is there a way to use SVG as content in a pseudo element :before or :after

我想将一些SVG图像放置在某些选定元素之前。 我正在使用jQuery,但这无关紧要。

我想将:before元素设置为:

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#mydiv:before {
  content: '<svg.. code here</svg>';
  display: block;
  width: 22px;
  height: 10px;
  margin: 10px 5px 0 10px;
}

如果我如上所示进行操作,它将仅显示字符串。 我检查了规格,似乎对内容有一些限制。 是否可以解决此限制? 只有内容CSS与我的问题有关。


是的你可以!刚刚测试过,效果很好,太棒了!它仍然不能与html一起使用,但可以与svg一起使用。

在我的index.html中,我有:

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我的test.svg看起来像这样:

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<svg xmlns="http://www.w3.org/2000/svg">
   <circle cx="100" cy="50" r="40" stroke="black" stroke-width="2" fill="red"/>
   <polyline points="20,20 40,25 60,40 80,120 120,140 200,180" style="fill:none;stroke:black;stroke-width:3"/>
</svg>


您可以将SVG添加为空的:after:beforebackground-image

干得好:

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.anchor:before {
  display: block;
  content: ' ';
  background-image: url('../images/anchor.svg');
  background-size: 28px 28px;
  height: 28px;
  width: 28px;
}


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#mydiv:before {
    content: url("data:image/svg+xml; utf8, <svg.. code here</svg>");
    display:block;
    width:22px;
    height:10px;
    margin:10px 5px 0 10px;
}

确保您的svg不包含双引号,并对所有#个符号进行uriencode。


利用CSS精灵和数据uri可以带来额外的有趣好处,例如快速加载和减少请求,并且通过使用image / base64获得IE8支持:

使用SVG的Codepen样本

的HTML

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的CSS

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.div1:after, .div2:after {
  content: '';
  display: block;
  height: 80px;
  width: 80px;
  background-image: url(data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20version%3D%221.1%22%20height%3D%2280%22%20width%3D%22160%22%3E%0D%0A%20%20%3Ccircle%20cx%3D%2240%22%20cy%3D%2240%22%20r%3D%2238%22%20stroke%3D%22black%22%20stroke-width%3D%221%22%20fill%3D%22red%22%20%2F%3E%0D%0A%20%20%3Ccircle%20cx%3D%22120%22%20cy%3D%2240%22%20r%3D%2238%22%20stroke%3D%22black%22%20stroke-width%3D%221%22%20fill%3D%22blue%22%20%2F%3E%0D%0A%3C%2Fsvg%3E);
}
.div2:after {
  background-position: -80px 0;
}

对于IE8,更改为:

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  background-image: url(data:image/png;base64,data......);


1
Lord Byron

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.author_ {  font-family: 'Playfair Display', serif; font-size: 1.25em; font-weight: 700;letter-spacing: 0.25em; font-style: italic;
  position:relative;
  margin-top: -0.5em;
  color: black;
  z-index:1;
  overflow:hidden;
  text-align:center;
 
}


.author_:after{
   left:20px;
  margin:0 -100% 0 0;
  display: inline-block;
  height: 10px;
  content: url(data:image/svg+xml,%0A%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%22120px%22%20height%3D%2220px%22%20viewBox%3D%220%200%201200%20200%22%20xmlns%3Axlink%3D%22http%3A%2F%2Fwww.w3.org%2F1999%2Fxlink%22%3E%0A%20%20%3Cpath%20stroke%3D%22black%22%20stroke-width%3D%223%22%20fill%3D%22none%22%20d%3D%22M1145%2085c17%2C7%208%2C24%20-4%2C29%20-12%2C4%20-40%2C6%20-48%2C-8%20-9%2C-15%209%2C-34%2026%2C-42%2017%2C-7%2045%2C-6%2062%2C2%2017%2C9%2019%2C18%2020%2C27%201%2C9%200%2C29%20-27%2C52%20-28%2C23%20-52%2C34%20-102%2C33%20-49%2C0%20-130%2C-31%20-185%2C-50%20-56%2C-18%20-74%2C-21%20-96%2C-23%20-22%2C-2%20-29%2C-2%20-56%2C7%20-27%2C8%20-44%2C17%20-44%2C17%20-13%2C5%20-15%2C7%20-40%2C16%20-25%2C9%20-69%2C14%20-120%2C11%20-51%2C-3%20-126%2C-23%20-181%2C-32%20-54%2C-9%20-105%2C-20%20-148%2C-23%20-42%2C-3%20-71%2C1%20-104%2C5%20-34%2C5%20-65%2C15%20-98%2C22%22%2F%3E%0A%3C%2Fsvg%3E%0A);
}
.author_:before {
  right:20px;
  margin:0 0 0 -100%;
  display: inline-block;
  height: 10px;
  content: url(data:image/svg+xml,%0A%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%22120px%22%20height%3D%2220px%22%20viewBox%3D%220%200%201200%20130%22%20xmlns%3Axlink%3D%22http%3A%2F%2Fwww.w3.org%2F1999%2Fxlink%22%3E%0A%20%20%3Cpath%20stroke%3D%22black%22%20stroke-width%3D%223%22%20fill%3D%22none%22%20d%3D%22M55%2068c-17%2C6%20-8%2C23%204%2C28%2012%2C5%2040%2C7%2048%2C-8%209%2C-15%20-9%2C-34%20-26%2C-41%20-17%2C-8%20-45%2C-7%20-62%2C2%20-18%2C8%20-19%2C18%20-20%2C27%20-1%2C9%200%2C29%2027%2C52%2028%2C23%2052%2C33%20102%2C33%2049%2C-1%20130%2C-31%20185%2C-50%2056%2C-19%2074%2C-21%2096%2C-23%2022%2C-2%2029%2C-2%2056%2C6%2027%2C8%2043%2C17%2043%2C17%2014%2C6%2016%2C7%2041%2C16%2025%2C9%2069%2C15%20120%2C11%2051%2C-3%20126%2C-22%20181%2C-32%2054%2C-9%20105%2C-20%20148%2C-23%2042%2C-3%2071%2C1%20104%2C6%2034%2C4%2065%2C14%2098%2C22%22%2F%3E%0A%3C%2Fsvg%3E%0A);
}
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\tLord Byron

SVG编码url-encoder的便捷工具


进一步扩展该主题。如果您想添加Font Awesome 5图标,则需要添加一些额外的CSS。

默认情况下,图标具有类svg-inline--fafa-w-*

也有修饰符类,例如fa-lgfa-rotate-*和其他。您需要检查svg-with-js.css文件并为此找到合适的CSS。

您需要为CSS图标添加自己的颜色,否则默认情况下它将为黑色,例如fill='%23f00',其中%23被编码为#

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h1::before{

  /* svg-inline--fa */
  display:inline-block;
  font-size:inherit;
  height:1em;
  overflow:visible;
  vertical-align:-.125em;
 
  /* fa-w-14 */
  width:.875em;
 
  /* Icon */
  content:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 448 512'%3E%3Cpath fill='%23f00' d='M400 256H152V152.9c0-39.6 31.7-72.5 71.3-72.9 40-.4 72.7 32.1 72.7 72v16c0 13.3 10.7 24 24 24h32c13.3 0 24-10.7 24-24v-16C376 68 307.5-.3 223.5 0 139.5.3 72 69.5 72 153.5V256H48c-26.5 0-48 21.5-48 48v160c0 26.5 21.5 48 48 48h352c26.5 0 48-21.5 48-48V304c0-26.5-21.5-48-48-48zM264 408c0 22.1-17.9 40-40 40s-40-17.9-40-40v-48c0-22.1 17.9-40 40-40s40 17.9 40 40v48z'%3E%3C/path%3E%3C/svg%3E");
 
  /* Margin */
  margin-right:.75rem;
}
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Lorem Ipsum


小心所有其他答案在IE中都存在一些问题。

让我们来看看这种情况-带前置图标的按钮。所有浏览器都可以正确处理此问题,但是IE会采用元素的宽度并缩放之前的内容以适合它。 JSFiddle

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#mydiv1 { width: 200px; height: 30px; background: green; }
#mydiv1:before {
    content: url("data:url or /standard/url.svg");
}

解决方案是将size设置为element之前,然后将其保留在原处:

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#mydiv2 { width: 200px; height: 30px; background: green; }
#mydiv2:before {
    content: url("data:url or /standard/url.svg");
    display: inline-block;
    width: 16px; //only one size is alright, IE scales uniformly to fit it
}

background-image + background-size解决方案也可以使用,但是有点麻烦,因为您必须两次指定相同的大小。

IE11中的结果:

IE rendering


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.myDiv {
  display: flex;
  align-items: center;
}

.myDiv:before {
  display: inline-block;
  content: url(./dog.svg);
  margin-right: 15px;
  width: 10px;
}