网页特效_拖拽案例

【教学视频】网页特效_拖拽案例：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        *{margin:0;padding:0;}
        #screen {
            display: none;
            width: 100%;
            height: 100%;
            background-color: rgba(0,0,0,.2);
            position: fixed;
            z-index: 999;
        }
        .nva {
            width: 100%;
            height: 50px;
            padding-left: 20px;
            background-color:#369;
        }
        .nva a {
            display: block;
            height: 50px;
            width: 100px;
            text-align: center;
            line-height: 50px;
            text-decoration: none;
            color: #FFF;
        }
        .box {
            display: none;
            width: 350px;
            height: 350px;
            background-color: white;
            border:5px solid #eee;
            box-shadow:2px 2px 2px 2px #666;
            position: fixed;
            top: 50%;
            left: 50%;
            margin-left: -175px;
            margin-top: -175px;
            z-index: 1000;
        }
        .box .cont {
            height: 30px;
            background-color: #7c9299;
            cursor: move;
        }
        .cont span {
            display: block;
            height: 30px;
            color: white;
            font: 500 14px/30px "微软雅黑";
        }
        .cont span.cl {
            padding-left: 10px;
            float: left;
        }
        .cont span.cr {
            width: 60px;
            float: right;
            cursor: pointer;
        }
    </style>
</head>
<body>
<div id="screen"></div>

<div class="nva" id="nva">
    <a href="javascript:;">注册信息</a>
</div>
<div class="box" id="box">
    <div class="cont">
        <span class="cl">注册信息(可以拖拽)</span>
        <span class="cr">【关闭】</span>
    </div>
</div>
</body>
</html>
<script>
    var screen = document.getElementById("screen");
    var zc = document.getElementById("nva").children[0];
    var box = document.getElementById("box");
    var cont = box.children[0];
    var close = cont.children[1];
    close.onclick = function() {
        screen.style.display = "none";
        box.style.display = "none";
    }
    zc.onclick = function() {
        screen.style.display = "block";
        box.style.display = "block";
    }

    //  current代表被点击的对象，move代表移动的对象
    function tuodong(current,move) {
        current.onmousedown = function(event) {
            var event = event || window.event;
            console.log(this.offsetLeft);
            // 被点击时的位置
            var valx = event.clientX - move.offsetLeft;
            var valy = event.clientY - move.offsetTop;
            document.onmousemove = function(event) {
                var event = event || window.event;
                var x = event.clientX - valx + move.offsetWidth / 2; // 加上175的margin-left
                var y = event.clientY - valy + move.offsetHeight / 2;
                move.style.left = x + "px";
                move.style.top = y + "px";

                // 清除选择拖动，不写这句话，会出现如果滑的快，弹起后依旧跟着鼠标走
                window.getSelection ? window.getSelection().removeAllRanges() : document.selection.empty();
            }
            document.onmouseup = function() {
                document.onmousemove = null;
            }
        }
    }

    tuodong(cont,box);

</script>

前进时，请别遗忘了身后的脚印。

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原文地址：https://www.cnblogs.com/liudaihuablogs/p/9457135.html