>页面尺寸
>>宽高尺寸
clientWidth / clientHeight窗口的宽度高度
scrollWidth / scrollHeight文档内容的高度宽度
offsetWidth / offsetHeight文档内容的高度宽度
>>坐标位置
scrollleft / scrollTop滚轴的水平便宜距离,垂直偏移距离
offsetLeft / offsetTop对象与页面的边距
event.clientX / event.clientY事件触发时,鼠标指针对窗口的水平垂直坐标(event为时间)
//注意事项:documentElement是整个节点树的根节点root,即html标签,document.body也是document能直接调用的属性标签
语法:
object.offsetLeft/oobject.offsetTop
>拖拽功能的实现
<html>
<head>
<meta charset="UTF-8">
<title>event</title>
<style>
#box {
width: 100px;
height: 100px;
background-color: aquamarine;
position: absolute;
}
</style>
</head>
<body>
<div id="box"></div>
<script type="text/javascript">
var oDiv = document.getElementById("box");
oDiv.onmousedown = function(ev){
var oEvent = ev;
var disX = oEvent.clientX-oDiv.offsetLeft;
var disY = oEvent.clientY-oDiv.offsetTop;
document.onmousemove = function(ev){
oEvent = ev;
oDiv.style.left = oEvent.clientX - disX +"px";
oDiv.style.top = oEvent.clientY - disY +"px";
}
document.onmouseup = function(){
document.onmousemove = null;
document.onmouseup = null;
}
}
</script>
</body>
</html>
//等待认真学习中... ...