HTML原生JavaScript实现Y轴拖动，可以左右拖动

2023-4-08 10:15

524

youhei

143 字

6 分钟

位置会自适应调整根据#parent的高度进行自动计算

<!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>拖动</title>
</head>
<style>
    * {
        margin: 0;
        padding: 0;
    }

    #parent {
        margin-top: 100px;
        width: 300px;
        height: 250px;
        border: 1px solid #ccc;
        overflow: auto;
    }

    #drag {
        width: 10%;
        height: 10%;
        background-color: #007bff;
        color: #fff;
        text-align: center;
        line-height: 50px;
        cursor: move;
        position: relative;
    }

    #switch {
        border: none;
        margin-top: 10px;
        padding: 10px;
        background-color: #007bff;
        color: #fff;
        text-align: center;

    }

    .box {
        margin-left: 30%;
    }
</style>

<body>
    <div id="parent" class="box">
        <div id="drag"></div>

    </div>
    <div class="box">
        <button id="switch">切换位置</button>
        <p id="location">位置</p>
    </div>

    <script>
        // 获取父元素和拖动元素
        var parent = document.getElementById("parent");
        var drag = document.getElementById("drag");
        var switchBtn = document.getElementById("switch");

        // 定义初始变量
        var isDragging = false;
        var dragStart = 0;
        var dragOffset = 0;
        var isLeft = true;

        // 监听鼠标按下事件
        drag.addEventListener("mousedown", function (event) {
            isDragging = true;
            dragStart = event.clientY;
            dragOffset = drag.offsetTop - parent.getBoundingClientRect().top;
        });
        // 监听鼠标移动事件
        document.addEventListener("mousemove", function (event) {
            let parentHeight = parent.clientHeight;
            if (isDragging) {
                let dragPos = event.clientY - dragStart + dragOffset;
                if (dragPos < 0) {
                    dragPos = 0;
                }
                if (dragPos > parent.clientHeight - drag.clientHeight) {
                    dragPos = parent.clientHeight - drag.clientHeight;
                }
                let location = document.getElementById("location");
                let locationV = parseInt(dragPos / (parentHeight / 100)); 
                location.innerText = "位置：" + locationV + "%";
                drag.style.top = dragPos + "px";
                parent.scrollTop = dragPos;
            }
        });

        // 监听鼠标松开事件
        document.addEventListener("mouseup", function () {
            isDragging = false;
        });

        // 监听切换按钮点击事件
        switchBtn.addEventListener("click", function () {
            isLeft = !isLeft;
            let switchText = isLeft ? "切换位置" : "切换位置";
            switchBtn.innerText = switchText;
            if (isLeft) {
                drag.style.left = "0";
            } else {
                drag.style.left = parent.clientWidth - drag.clientWidth + "px";
            }
        });
    </script>
</body>


</html>

效果图：