Native JS-Implementierungsmethode zur Bestimmung von Kollisionen (interessantes Beispiel)

<div id="d1"></div>  
<div id="d2"></div>

<style type="text/css">  
        * {  
            padding: 0px;  
            margin: 0px;  
         }  
        #d1{  
            width: 100px;  
            height: 100px;  
            background: red;  
            position: absolute;  
        }  
        #d2{  
            width: 200px;  
            height: 200px;  
            background: yellow;  
            position: absolute;  
            top: 200px;  
            left: 400px;  
            position: absolute;  
        }  
</style>

<script type="text/javascript">  
    div=document.querySelectorAll("div");   
function hit(obj){  
    obj.onmousedown=function(e){  
        var e=e||window.event;  
        var dX=e.offsetX;  
        var dY=e.offsetY;  
        document.onmousemove=function(e){  
            var x=e.clientX;  
            var y=e.clientY;  
            obj.style.left=x-dX+"px";  
            obj.style.top=y-dY+"px";  
            if(div[0].offsetTop+div[0].offsetHeight>=div[1].offsetTop && div[0].offsetTop<=div[1].offsetTop+div[1].offsetHeight && div[0].offsetLeft+div[0].offsetWidth>=div[1].offsetLeft && div[0].offsetLeft<=div[1].offsetLeft+div[1].offsetWidth){  
                console.log("你撞我了！再撞一个试试！")  
            };  
    }  
    document.onmouseup=function(){  
        document.onmousemove=null;  
    }  
}     
}  
hit(div[0]);  
hit(div[1]);  
</script>