js手机手写签名

<canvas id="signatureCanvas" width="300" height="200"></canvas>

<script>
  const canvas = document.getElementById('signatureCanvas');
  const ctx = canvas.getContext('2d');
  let isDrawing = false;

  canvas.addEventListener('touchstart', (e) => {
    isDrawing = true;
    const touch = e.touches[0];
    ctx.beginPath();
    ctx.moveTo(touch.clientX - canvas.offsetLeft, touch.clientY - canvas.offsetTop);
  });

  canvas.addEventListener('touchmove', (e) => {
    if (isDrawing) {
      const touch = e.touches[0];
      ctx.lineTo(touch.clientX - canvas.offsetLeft, touch.clientY - canvas.offsetTop);
      ctx.stroke();
    }
  });

  canvas.addEventListener('touchend', () => {
    isDrawing = false;
  });
</script>