用纯css填充较低的输入范围？

Question

我正在尝试找到一种方法来填充范围输入的下部以显示进度，而不使用 JS 来更新渐变。

这是我的 js 代码：

<input id="slider" type="range" min="1" max="100" value={_volume} className={styles.slider} onChange={(e)=> this.setState({ _volume: parseInt(e.target.value) })} />

这是我的css代码：

.slider {
  background: linear-gradient(to right, $lightGrey 0%, $lightGrey 50%, $darkGrey 50%, $darkGrey 100%);
  border: none;
  border-radius: 4px;
  height: 3px;
  width: 100%;
  outline: none;
  transition: background 450ms ease-in;
  -webkit-appearance: none;
}

.slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 10px;
  height: 10px;
  background: $lightGrey;
  border-radius: 50%;
  cursor: pointer;
  z-index: 2;
}

Answer 1

据我所知，没有 JS 是不可能的。

有一种简单的替代方法，只需一点点 JS。
使用这个：https://toughengineer.github.io/demo/slider-styler

for (let e of document.querySelectorAll('input[type="range"].slider-progress')) {
  e.style.setProperty('--value', e.value);
  e.style.setProperty('--min', e.min == '' ? '0' : e.min);
  e.style.setProperty('--max', e.max == '' ? '100' : e.max);
  e.addEventListener('input', () => e.style.setProperty('--value', e.value));
}

/*generated with Input range slider CSS style generator (version 20201223)
https://toughengineer.github.io/demo/slider-styler*/
input[type=range].styled-slider {
  height: 2.2em;
  -webkit-appearance: none;
}

/*progress support*/
input[type=range].styled-slider.slider-progress {
  --range: calc(var(--max) - var(--min));
  --ratio: calc((var(--value) - var(--min)) / var(--range));
  --sx: calc(0.5 * 2em + var(--ratio) * (100% - 2em));
}

input[type=range].styled-slider:focus {
  outline: none;
}

/*webkit*/
input[type=range].styled-slider::-webkit-slider-thumb {
  width: 2em;
  height: 2em;
  border-radius: 1em;
  background: #007cf8;
  border: none;
  box-shadow: 0 0 2px black;
  margin-top: calc(max((1em - 1px - 1px) * 0.5,0px) - 2em * 0.5);
  -webkit-appearance: none;
}

input[type=range].styled-slider::-webkit-slider-runnable-track {
  height: 1em;
  border-radius: 0.5em;
  background: #efefef;
  border: 1px solid #b2b2b2;
  box-shadow: none;
}
input[type=range].styled-slider::-webkit-slider-thumb:hover {
  background: #0061c3;
}

input[type=range].styled-slider:hover::-webkit-slider-runnable-track {
  background: #e5e5e5;
  border-color: #9a9a9a;
}

input[type=range].styled-slider::-webkit-slider-thumb:active {
  background: #2f98f9;
}

input[type=range].styled-slider:active::-webkit-slider-runnable-track {
  background: #f5f5f5;
  border-color: #c1c1c1;
}

input[type=range].styled-slider.slider-progress::-webkit-slider-runnable-track {
  background: linear-gradient(#007cf8,#007cf8) 0/var(--sx) 100% no-repeat, #efefef;
}

input[type=range].styled-slider.slider-progress:hover::-webkit-slider-runnable-track {
  background: linear-gradient(#0061c3,#0061c3) 0/var(--sx) 100% no-repeat, #e5e5e5;
}

input[type=range].styled-slider.slider-progress:active::-webkit-slider-runnable-track {
  background: linear-gradient(#2f98f9,#2f98f9) 0/var(--sx) 100% no-repeat, #f5f5f5;
}

/*mozilla*/
input[type=range].styled-slider::-moz-range-thumb {
  width: 2em;
  height: 2em;
  border-radius: 1em;
  background: #007cf8;
  border: none;
  box-shadow: 0 0 2px black;
}

input[type=range].styled-slider::-moz-range-track {
  height: max(calc(1em - 1px - 1px),0px);
  border-radius: 0.5em;
  background: #efefef;
  border: 1px solid #b2b2b2;
  box-shadow: none;
}

input[type=range].styled-slider::-moz-range-thumb:hover {
  background: #0061c3;
}

input[type=range].styled-slider:hover::-moz-range-track {
  background: #e5e5e5;
  border-color: #9a9a9a;
}

input[type=range].styled-slider::-moz-range-thumb:active {
  background: #2f98f9;
}

input[type=range].styled-slider:active::-moz-range-track {
  background: #f5f5f5;
  border-color: #c1c1c1;
}

input[type=range].styled-slider.slider-progress::-moz-range-track {
  background: linear-gradient(#007cf8,#007cf8) 0/var(--sx) 100% no-repeat, #efefef;
}

input[type=range].styled-slider.slider-progress:hover::-moz-range-track {
  background: linear-gradient(#0061c3,#0061c3) 0/var(--sx) 100% no-repeat, #e5e5e5;
}

input[type=range].styled-slider.slider-progress:active::-moz-range-track {
  background: linear-gradient(#2f98f9,#2f98f9) 0/var(--sx) 100% no-repeat, #f5f5f5;
}

/*ms*/
input[type=range].styled-slider::-ms-fill-upper {
  background: transparent;
  border-color: transparent;
}

input[type=range].styled-slider::-ms-fill-lower {
  background: transparent;
  border-color: transparent;
}

input[type=range].styled-slider::-ms-thumb {
  width: 2em;
  height: 2em;
  border-radius: 1em;
  background: #007cf8;
  border: none;
  box-shadow: 0 0 2px black;
  margin-top: 0;
  box-sizing: border-box;
}

input[type=range].styled-slider::-ms-track {
  height: 1em;
  border-radius: 0.5em;
  background: #efefef;
  border: 1px solid #b2b2b2;
  box-shadow: none;
  box-sizing: border-box;
}

input[type=range].styled-slider::-ms-thumb:hover {
  background: #0061c3;
}

input[type=range].styled-slider:hover::-ms-track {
  background: #e5e5e5;
  border-color: #9a9a9a;
}

input[type=range].styled-slider::-ms-thumb:active {
  background: #2f98f9;
}

input[type=range].styled-slider:active::-ms-track {
  background: #f5f5f5;
  border-color: #c1c1c1;
}

input[type=range].styled-slider.slider-progress::-ms-fill-lower {
  height: max(calc(1em - 1px - 1px),0px);
  border-radius: 0.5em 0 0 0.5em;
  margin: -1px 0 -1px -1px;
  background: #007cf8;
  border: 1px solid #b2b2b2;
  border-right-width: 0;
}

input[type=range].styled-slider.slider-progress:hover::-ms-fill-lower {
  background: #0061c3;
  border-color: #9a9a9a;
}

input[type=range].styled-slider.slider-progress:active::-ms-fill-lower {
  background: #2f98f9;
  border-color: #c1c1c1;
}

<input type="range" class="styled-slider slider-progress" style="width: 30em;" />