HTML5拖拽功能实现的拼图游戏

具体代码如下所示：

<!--代码如下，最下面给出了我测试用的9张250*250的图片切片--><!DOCTYPE html><html><head>    <meta charset="utf-8">    <title>drag拖拽</title>    <style>        .box{             float: left;        }        img{            width: 150px;            height:150px;        }        #puzzle{            font-size: 0;            margin:80px auto;            padding: 5px;            width: 460px;        }    </style></head><body>    <div id="puzzle">        <div class="box"><img alt="1"></div>        <div class="box"><img alt="2"></div>        <div class="box"><img alt="3"></div>        <div class="box"><img alt="4"></div>        <div class="box"><img alt="5"></div>        <div class="box"><img alt="6"></div>        <div class="box"><img alt="7"></div>        <div class="box"><img alt="8"></div>        <div class="box"><img alt="9"></div>    </div>    <script>        var image = document.getElementsByTagName("img");        var box = document.getElementsByClassName("box");        image.draggable = true;        var source = "";        var nowImage;        var nowImageBox;        var thenImage;        for(let i=0;i<image.length;i++){            source = "picture"+i+".jpg";            image[i].setAttribute("src",source);            image[i].onmousedown = function(){                nowImage = this;                nowImageBox = this.parentNode;            }            box[i].ondragover = function(event){             event.preventDefault(); //去除ondragover事件的默认行为，该行为默认无法将数据或者元素放置到其他元素            }            box[i].ondrop = function(event){                thenImage = box[i].childNodes[0];                box[i].appendChild(nowImage);                nowImageBox.appendChild(thenImage);            }        }    </script></body></html>