用canvas写一个股票箭头上升的动态路径特效

好的，以下是一个简单的用canvas实现股票箭头上升的动态路径特效的代码：

<canvas id="myCanvas"></canvas>

const canvas = document.getElementById('myCanvas');
const ctx = canvas.getContext('2d');

// 设置画布大小
canvas.width = 400;
canvas.height = 400;

// 绘制箭头
function drawArrow(x, y, width, height) {
  ctx.beginPath();
  ctx.moveTo(x, y);
  ctx.lineTo(x + width / 2, y + height);
  ctx.lineTo(x - width / 2, y + height);
  ctx.closePath();
  ctx.fill();
}

// 绘制路径
function drawPath() {
  ctx.beginPath();
  ctx.moveTo(50, 350);
  ctx.lineTo(150, 250);
  ctx.lineTo(250, 350);
  ctx.strokeStyle = '#000';
  ctx.lineWidth = 5;
  ctx.stroke();
}

// 动态绘制箭头
let arrowX = 50;
let arrowY = 350;
let arrowWidth = 30;
let arrowHeight = 50;
let arrowDirection = 1;

function animateArrow() {
  ctx.clearRect(0, 0, canvas.width, canvas.height);
  drawPath();
  drawArrow(arrowX, arrowY, arrowWidth, arrowHeight);

  if (arrowX >= 250) {
    arrowDirection = -1;
  } else if (arrowX <= 50) {
    arrowDirection = 1;
  }

  arrowX += arrowDirection * 5;

  requestAnimationFrame(animateArrow);
}

animateArrow();

这段代码会在画布上绘制一条路径和一个箭头，箭头会沿着路径上下移动。