html扑克牌展开,HTML5 canvas扑克牌花式洗牌动画

展开扑克牌的 HTML 代码如下：

<div class="card">
  <div class="card-face front"></div>
  <div class="card-face back"></div>
</div>

其中，`.card` 是扑克牌的容器，`.front` 和 `.back` 是扑克牌的正反面。

通过 CSS 样式设置 `.card` 的宽高、边框、背景色等属性，以及 `.front` 和 `.back` 的背景图案，就可以实现扑克牌的展开效果。

至于 HTML5 canvas 扑克牌花式洗牌动画，需要使用 canvas 的绘图 API 实现。具体的实现过程比较复杂，需要涉及到 canvas 的基本操作、动画效果、事件处理等内容。以下是一个简单的示例：

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

const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');
const width = canvas.width = window.innerWidth;
const height = canvas.height = window.innerHeight;
const cards = [];

// 加载扑克牌的图片资源
const cardImages = [];
for (let i = 0; i < 52; i++) {
  const img = new Image();
  img.src = `cards/${i}.png`;
  cardImages.push(img);
}

// 创建扑克牌对象
class Card {
  constructor(image, x, y) {
    this.image = image;
    this.x = x;
    this.y = y;
    this.angle = 0;
    this.spin = 0;
    this.targetAngle = 0;
    this.targetX = 0;
    this.targetY = 0;
    this.isMoving = false;
  }
  draw() {
    ctx.save();
    ctx.translate(this.x, this.y);
    ctx.rotate(this.angle);
    ctx.drawImage(this.image, -50, -75, 100, 150);
    ctx.restore();
  }
  update() {
    if (this.isMoving) {
      const dx = this.targetX - this.x;
      const dy = this.targetY - this.y;
      const distance = Math.sqrt(dx * dx + dy * dy);
      if (distance < 1) {
        this.isMoving = false;
        this.x = this.targetX;
        this.y = this.targetY;
        this.angle = this.targetAngle;
      } else {
        const speed = 5;
        const angle = Math.atan2(dy, dx);
        this.x += Math.cos(angle) * speed;
        this.y += Math.sin(angle) * speed;
        this.angle += this.spin * speed;
      }
    }
  }
  moveTo(x, y, angle, spin) {
    this.isMoving = true;
    this.targetX = x;
    this.targetY = y;
    this.targetAngle = angle;
    this.spin = spin;
  }
}

// 初始化扑克牌
for (let i = 0; i < 52; i++) {
  const x = width / 2 + Math.random() * 200 - 100;
  const y = height / 2 + Math.random() * 200 - 100;
  const card = new Card(cardImages[i], x, y);
  cards.push(card);
}

// 动画循环
function loop() {
  ctx.clearRect(0, 0, width, height);
  for (let i = 0; i < cards.length; i++) {
    cards[i].update();
    cards[i].draw();
  }
  requestAnimationFrame(loop);
}

// 点击画布，触发洗牌动画
canvas.addEventListener('click', () => {
  let delay = 0;
  for (let i = 0; i < cards.length; i++) {
    const card = cards[i];
    const x = width / 2 + Math.random() * 200 - 100;
    const y = height / 2 + Math.random() * 200 - 100;
    const angle = Math.random() * Math.PI * 2;
    const spin = Math.random() - 0.5;
    setTimeout(() => {
      card.moveTo(x, y, angle, spin);
    }, delay);
    delay += 10;
  }
});

// 开始动画循环
loop();

以上代码实现了一个简单的扑克牌洗牌动画。具体效果可以参考以下链接：

[HTML5 扑克牌花式洗牌动画](https://www.zhangxinxu.com/study/201712/html5-poker-canvas-shuffle-animation.html)