CSS:
<style> .container { width: 600px; height: 600px; border: 1px solid; display: flex; flex-wrap: wrap; margin: 100px auto; } .block { width: 33.33%; height: 33.33%; outline: 1px solid black; text-align: center; line-height: 200px; font-size: 26px; } .block5 { background-color: skyblue; cursor: pointer; } </style>
HTML:
<div class="container"> <div class="block1 block">北京</div> <div class="block2 block">上海</div> <div class="block3 block">广州</div> <div class="block4 block">深圳</div> <div class="block5 block">抽取</div> <div class="block6 block">武汉</div> <div class="block7 block">南京</div> <div class="block8 block">杭州</div> <div class="block9 block">西安</div> </div>
JS：
<script> let blocks = document.getElementsByClassName("block"); // 数组存放的是盒子的下标，按照顺时针的顺序 let arr = [0, 1, 2, 5, 8, 7, 6, 3], i = 0, count = 0, stopTimer; let rand = Math.floor(Math.random() * 8 + 50); // 给出一个停止计时器的随机数 count的值等于这个随机数时停止计时器 let around = function() { // 将其他盒子都变为白色 for (let j = 0; j < arr.length; j++) { blocks[arr[j]].style.background = "white"; } // 这里blocks的取值为 blocks[0] blocks[1] blocks[2] blocks[5] blocks[8] blocks[7] blocks[6] blocks[3] // 将当前arr[i]值所对应的盒子修改为粉色 blocks[arr[i]].style.background = "pink"; i++; // 重制i的值 if (i === arr.length) { i = 0; } count++; // count是一个计数器 根据count的值来调整速度 // 下面的4个if根据count的值来关闭计时器和重启计时器 改变计时器的时间间隔 if (count === 5 || count === 45) { clearInterval(stopTimer); stopTimer = setInterval(around, 200); } if (count === 10 || count === 35) { clearInterval(stopTimer); stopTimer = setInterval(around, 100); } if (count === 15) { clearInterval(stopTimer); stopTimer = setInterval(around, 50); } // 当等于上面的随机数时，停止计时器 if (count === rand) { clearInterval(stopTimer); } } // 给开始按钮绑定点击事件 点击后执行 around let start = function() { blocks[4].removeEventListener("click", start); // 当用户点击了开始按钮后 必须要移除该事件 防止用户重复点击 stopTimer = setInterval(around, 300); } blocks[4].addEventListener("click", start); </script>
