选项卡代码-优快云博客

本文链接：https://blog.youkuaiyun.com/weixin_53374733/article/details/126860748

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            margin: 0;
            padding: 0;
        }
        span{
            display: inline-block;
            width: 100px;
            height: 30px;
            font-size: 20px;
            line-height: 50x;
            text-align: center;
            background-color: gray;
            color: white;
            border-radius: 3px;
            /* 鼠标移入变小手 */
            cursor: pointer;
        }
        div{
            width: 309.5px;
            height: 309.5px;
            background-color: skyblue;
            font-size: 30px;
            display: none;
        }
    </style>
</head>

<body>
    <span>第一个</span>
    <span>第二个</span>
    <span>第三个</span>
    <div>1</div>
    <div>2</div>
    <div>3</div>
</body>
<script>
    // 1.获取元素
    var spans=document.getElementsByTagName('span')
    var divs=document.querySelectorAll('div')

    // 通过for循环便利 统一绑定事件
    for (var i = 0; i < spans.length; i++) {
        // /自定义属性 保存i值
        spans[i].index=i
        // i=0 i=1 i=2 i=3
        spans[i].onclick=function(){
            // 样式初始化
            for(var j=0;j<spans.length;j++){
                spans[j].style.backgroundColor='gray'
                divs[j].style.display='none'
            }
            console.log(i);
            // 3
            // console.log("我是span");
            // this谁绑定事件this就代表谁
            // console.log(this.index);
            console.log(divs[this.index]);
            divs[this.index].style.display='block'
            this.style.backgroundColor='black'
        }
        
    }
</script>
</html>