当前位置: 首页 > 图文教程 > 网络编程 > Javascript > 拖动一个HTML元素

Javascript
js 创建一个浮动div的代码
javascript下利用数组缓存正则表达式的实现方法
javascript 最常用的10个自定义函数[推荐]
jQuery 常见开发使用技巧总结
十分钟打造AutoComplete自动完成效果代码
JavaScript 入门基础知识 想学习js的朋友可以参考下
javascript 清空form表单中某种元素的值
javascript 格式化时间日期函数代码脚本之家修正版
javascript dom操作之cloneNode文本节点克隆使用技巧
jQuery 动态酷效果实现总结
jQuery中的常用事件总结
用Jquery实现可编辑表格并用AJAX提交到服务器修改数据
javascript+css 网页每次加载不同样式的实现方法
向大师们学习Javascript(视频与PPT)
js 实现无干扰阴影效果 简单好用(附文件下载)
JavaScript 拾漏补遗
IE6 弹出Iframe层中的文本框“经常”无法获得输入焦点
jQuery的强大选择器小结
jquery $(document).ready() 与window.onload的区别
javascript 动态调整图片尺寸实现代码

Javascript 中的 拖动一个HTML元素


出处:互联网   整理: 软晨网(RuanChen.com)   发布: 2009-09-12   浏览: 136 ::
收藏到网摘: n/a

<script content="text/javascript">
var iMouseDown = false;
var dragObject = null;
Number.prototype.NaN0=function(){return isNaN(this)?0:this;}
// Demo 0 variables
var DragDrops = [];
var curTarget = null;
var lastTarget = null;
function makeDraggable(item){
if(!item) return;
item.onmousedown = function(ev){
dragObject = this;
mouseOffset = getMouseOffset(this, ev);
return false;
}
}
function getMouseOffset(target, ev){
ev = ev || window.event;
var docPos = getPosition(target);
var mousePos = mouseCoords(ev);
return {x:mousePos.x - docPos.x, y:mousePos.y - docPos.y};
}
function getPosition(e){
var left = 0;
var top = 0;
while (e.offsetParent){
left += e.offsetLeft + (e.currentStyle?(parseInt(e.currentStyle.borderLeftWidth)).NaN0():0);
top += e.offsetTop + (e.currentStyle?(parseInt(e.currentStyle.borderTopWidth)).NaN0():0);
e = e.offsetParent;
}
left += e.offsetLeft + (e.currentStyle?(parseInt(e.currentStyle.borderLeftWidth)).NaN0():0);
top += e.offsetTop + (e.currentStyle?(parseInt(e.currentStyle.borderTopWidth)).NaN0():0);
return {x:left, y:top};
}
function mouseCoords(ev){
if(ev.pageX || ev.pageY){
return {x:ev.pageX, y:ev.pageY};
}
return {
x:ev.clientX + document.body.scrollLeft - document.body.clientLeft,
y:ev.clientY + document.body.scrollTop - document.body.clientTop
};
}
function mouseDown(ev){
ev = ev || window.event;
var target = ev.target || ev.srcElement;
if(target.onmousedown || target.getAttribute('DragObj')){
return false;
}
}
function mouseUp(ev){
//dragObject = null;
if(dragObject){
ev = ev || window.event;
var mousePos = mouseCoords(ev);
var dT = dragObject.getAttribute('droptarget');
if(dT){
var targObj = document.getElementById(dT);
var objPos = getPosition(targObj);
if((mousePos.x > objPos.x) && (mousePos.y > objPos.y)
&& (mousePos.x<(objPos.x+parseInt(targObj.offsetWidth)))
&& (mousePos.y<(objPos.y+parseInt(targObj.offsetHeight)))){
var nSrc = targObj.getAttribute('newSrc');
if(nSrc){
dragObject.src = nSrc;
setTimeout(function(){
if(!dragObject || !dragObject.parentNode) return;
dragObject.parentNode.removeChild(dragObject);
dragObject = null;
}, parseInt(targObj.getAttribute('timeout')));
} else {
dragObject.parentNode.removeChild(dragObject);
}
}
}
}
dragObject = null;
iMouseDown = false;
}
function mouseMove(ev){
ev = ev || window.event;
/*
We are setting target to whatever item the mouse is currently on
Firefox uses event.target here, MSIE uses event.srcElement
*/
var target = ev.target || ev.srcElement;
var mousePos = mouseCoords(ev);
if(dragObject){
dragObject.style.position = 'absolute';
dragObject.style.top = mousePos.y - mouseOffset.y;
dragObject.style.left = mousePos.x - mouseOffset.x;
}
// track the current mouse state so we can compare against it next time
lMouseState = iMouseDown;
// this prevents items on the page from being highlighted while dragging
if(curTarget || dragObject) return false;
}
function addDropTarget(item, target){
item.setAttribute('droptarget', target);
}
document.onmousemove = mouseMove;
document.onmousedown = mouseDown;
document.onmouseup = mouseUp;
window.onload = function (){
makeDraggable(document.getElementById('DragImage9'));
makeDraggable(document.getElementById('DragImage10'));
makeDraggable(document.getElementById('DragImage11'));
makeDraggable(document.getElementById('DragImage12'));
addDropTarget(document.getElementById('DragImage9'), 'TrashImage1');
addDropTarget(document.getElementById('DragImage10'), 'TrashImage1');
addDropTarget(document.getElementById('DragImage11'), 'TrashImage1');
addDropTarget(document.getElementById('DragImage12'), 'TrashImage1');
}
</script>
</head>
<body>
<fieldset id="Demo6" style="height: 70px"><h3>Demo - Drag any of the images</h3>
<img id="TrashImage1" src="http://www.cnlei.org/codes/javascript/js-drag-drop/images/drag_drop_trash.gif" />
<img id="DragImage9" src="http://www.cnlei.org/codes/javascript/js-drag-drop/images/drag_drop_spade.gif" />
<img id="DragImage10" src="http://www.cnlei.org/codes/javascript/js-drag-drop/images/drag_drop_heart.gif" />
<img id="DragImage11" src="http://www.cnlei.org/codes/javascript/js-drag-drop/images/drag_drop_diamond.gif" />
<img id="DragImage12" src="http://www.cnlei.org/codes/javascript/js-drag-drop/images/drag_drop_club.gif" />
</fieldset>