先看页面成果。上面四个按钮别离示意开始、完结、暂停、持续

上面是帧动画图片素材:

帧动画的实现,要害是Canvas API ctx.drawImage() (9个参数)和 setInterval 定时器。
设置图片的视图窗口,每次执行定时工作,位移展现下一帧图片。

间接上代码,Ctrl+C/V 即插即用

<!DOCTYPE html><html>    <head>        <meta charset="utf-8">        <title>帧动画</title>    </head>    <body>        <canvas id="canvas" width="400" height="300"></canvas>        <div class="">            <button class="start-btn" type="button">从新吃</button>            <button class="end-btn" type="button">不吃了</button>            <button class="pause-btn" type="button">歇一歇</button>            <button class="continue-btn" type="button">持续吃</button>        </div>        <script type="text/javascript">            const canvas = document.getElementById("canvas")            canvas.style.border = "1px solid black"            const ctx = canvas.getContext("2d")            const img = new Image() // 创立图片对象            let timer // 定时器标识符            let millisec = 300 // 执行工夫距离            let colIndex = 0 // 列数            let rowIndex = 0 // 行数            const timerFun = () => { // 申明定时器执行函数                console.log("设置定时器");                ctx.clearRect(0, 0, canvas.style.width, canvas.style.height) // 革除画布                if (rowIndex < 3) { // 如果是前5帧                    ctx.drawImage(img, colIndex * 240, rowIndex * 240, 200, 200, 50, 50, 200, 200) // 图片对象,x坐标,y坐标(注:图片上定位的坐标),width,height(图片上截取的大小),x坐标,y坐标(注:图片在画布上的终点,即左上角),width,height(缩放,不是裁剪)                    colIndex++ // 下一帧                    if (colIndex > 4) {                        colIndex = 0                        rowIndex++                    }                } else {                    colIndex = 0                    rowIndex = 0                }            }            img.onload = () => {                timer = setInterval(timerFun, millisec)            }            img.src = "image/apple.jpg"            const startBtn = document.getElementsByClassName('start-btn')[0]            const endBtn = document.getElementsByClassName('end-btn')[0]            const pauseBtn = document.getElementsByClassName('pause-btn')[0]            const continueBtn = document.getElementsByClassName('continue-btn')[0]            startBtn.addEventListener('click', () => {                console.log("点击开始", timer)                clearInterval(timer)                colIndex = 0 // 列数                rowIndex = 0 // 行数                timer = setInterval(timerFun, millisec)            })            endBtn.addEventListener('click', () => {                console.log("点击完结", timer)                clearInterval(timer)                colIndex = 0                rowIndex = 0                ctx.drawImage(img, colIndex * 240, rowIndex * 240, 200, 200, 50, 50, 200, 200)                timer = 0            })            pauseBtn.addEventListener('click', () => {                console.log("点击暂停", timer)                clearInterval(timer)                timer = 0            })            continueBtn.addEventListener('click', () => {                if (timer) {                    alert('吃着呢,别催')                    return                }                console.log("点击持续", timer)                timer = setInterval(timerFun, millisec)            })        </script>    </body></html>