如何使用Uniapp绘制横线

// 样式
.line {
  border-bottom: 1px solid #000; // 下边框
  height: 1px;
  margin-top: 10px;
}
// html
<view class="line"></view>

// html
<canvas style="width: 100%; height: 200px;" canvas-id='first-canvas'></canvas>
// js
onReady() {
  const query = uni.createSelectorQuery().in(this);
  query.select('#first-canvas').fields({
    node: true,
    size: true,
  }).exec((res) => {
    const canvas = res[0].node;
    const ctx = canvas.getContext('2d');
    const dpr = uni.getSystemInfoSync().pixelRatio;
    canvas.width = res[0].width * dpr;
    canvas.height = res[0].height * dpr;
    ctx.lineWidth = 1 * dpr;
    ctx.strokeStyle = '#000000';
    ctx.beginPath();
    ctx.moveTo(0, 100 * dpr);
    ctx.lineTo(canvas.width, 100 * dpr);
    ctx.stroke();
  });
}