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+``` +```css +.box::after{ + content: attr(abc); +} +``` + +#### 同时显示出alt信息 +利用attr函数,就可以做点比较酷的效果了 +```html +这里是个提示 +``` +```css +img.error { + display: inline-block; + position: relative; +} +img.error::before { + content: ''; + background: #FFF url('break.svg') no-repeat; + background-position: center; + background-size: cover; + height: 100%; + width: 100%; + position: absolute; + left: 0; + top: 0; +} +img.error::after { + content: attr(alt); + position: absolute; + background: rgba(0, 0, 0, 0.6); + width: 100%; + bottom: 0; + left: 0; + text-align: center; + color: #FFF; + padding: 5px; +} +``` +效果 +![显示alt内容](/images/前端杂烩/显示alt内容.jpg) \ No newline at end of file