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Javascript
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prototype与jquery下Ajax实现的差别
用JS写的简单的计算器实现代码
javascript 数组操作实用技巧
JavaScript 中级笔记 第二章
JavaScript 中级笔记 第三章
JavaScript 中级笔记 第四章 闭包
JavaScript 中级笔记 第五章 面向对象的基础
Mootools 1.2教程 函数
Mootools 1.2教程 事件处理
通过Mootools 1.2来操纵HTML DOM元素
Mootools 1.2教程 设置和获取样式表属性
Mootools 1.2教程 输入过滤第一部分(数字)
Mootools 1.2教程 输入过滤第二部分(字符串)
Mootools 1.2教程 Fx.Tween的使用
Mootools 1.2教程 Fx.Morph、Fx选项和Fx事件
MooTools 1.2中的Drag.Move来实现拖放
Mootools 1.2教程 正则表达式
Mootools 1.2教程 定时器和哈希简介
Mootools 1.2教程 滚动条(Slider)

Javascript 中的 拖动一个HTML元素


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<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>