实现1
参考文献：http://www.cnblogs.com/cloudgamer/archive/2008/11/17/Drag.html
1.1 拖放效果
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <!-- saved from url=(0037)http://sandbox.runjs.cn/show/hbhrnv2g --> <html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title> 拖放效果 </title> </head> <body> <div id="idContainer" style="position: relative;"> <div id="idDrag" style="position: absolute;"> <div id="idHandle"> </div> </div> </div> <input id="idReset" type="button" value="复位"> <input id="idLock" type="button" value="锁定"> <input id="idLockX" type="button" value="锁定水平"> <input id="idLockY" type="button" value="锁定垂直"> <input id="idLimit" type="button" value="范围锁定"> <input id="idLimitOff" type="button" value="取消范围锁定"> <br> 拖放状态： <span id="idShow"> 未开始 </span> <style>#idContainer{ border:10px solid #990000; width:600px; height:300px; } #idDrag{ border:5px solid #C4E3FD; background:#C4E3FD; width:50px; height:50px; top:50px; left:50px; } #idHandle{ cursor:move; height:25px; background:#0000FF; overflow:hidden; }</style> <script>//以下是实现的插件 var isIE = (document.all) ? true: false; var $ = function(id) { return "string" == typeof id ? document.getElementById(id) : id; }; var Class = { create: function() { return function() { this.initialize.apply(this, arguments); } } } var Extend = function(destination, source) { for (var property in source) { destination[property] = source[property]; } } var Bind = function(object, fun) { return function() { return fun.apply(object, arguments); } } var BindAsEventListener = function(object, fun) { return function(event) { return fun.call(object, (event || window.event)); } } var CurrentStyle = function(element) { return element.currentStyle || document.defaultView.getComputedStyle(element, null); } function addEventHandler(oTarget, sEventType, fnHandler) { if (oTarget.addEventListener) { oTarget.addEventListener(sEventType, fnHandler, false); } else if (oTarget.attachEvent) { oTarget.attachEvent("on" + sEventType, fnHandler); } else { oTarget["on" + sEventType] = fnHandler; } }; function removeEventHandler(oTarget, sEventType, fnHandler) { if (oTarget.removeEventListener) { oTarget.removeEventListener(sEventType, fnHandler, false); } else if (oTarget.detachEvent) { oTarget.detachEvent("on" + sEventType, fnHandler); } else { oTarget["on" + sEventType] = null; } }; //拖放程序 var Drag = Class.create(); Drag.prototype = { //拖放对象 initialize: function(drag, options) { this.Drag = $(drag); //拖放对象 this._x = this._y = 0; //记录鼠标相对拖放对象的位置 this._marginLeft = this._marginTop = 0; //记录margin //事件对象(用于绑定移除事件) this._fM = BindAsEventListener(this, this.Move); this._fS = Bind(this, this.Stop); this.SetOptions(options); this.Limit = !!this.options.Limit; this.mxLeft = parseInt(this.options.mxLeft); this.mxRight = parseInt(this.options.mxRight); this.mxTop = parseInt(this.options.mxTop); this.mxBottom = parseInt(this.options.mxBottom); this.LockX = !!this.options.LockX; this.LockY = !!this.options.LockY; this.Lock = !!this.options.Lock; this.onStart = this.options.onStart; this.onMove = this.options.onMove; this.onStop = this.options.onStop; this._Handle = $(this.options.Handle) || this.Drag; this._mxContainer = $(this.options.mxContainer) || null; this.Drag.style.position = "absolute"; //透明 if (isIE && !!this.options.Transparent) { //填充拖放对象 with(this._Handle.appendChild(document.createElement("div")).style) { width = height = "100%"; backgroundColor = "#fff"; filter = "alpha(opacity:0)"; fontSize = 0; } } //修正范围 this.Repair(); addEventHandler(this._Handle, "mousedown", BindAsEventListener(this, this.Start)); }, //设置默认属性 SetOptions: function(options) { this.options = { //默认值 Handle: "", //设置触发对象（不设置则使用拖放对象） Limit: false, //是否设置范围限制(为true时下面参数有用,可以是负数) mxLeft: 0, //左边限制 mxRight: 9999, //右边限制 mxTop: 0, //上边限制 mxBottom: 9999, //下边限制 mxContainer: "", //指定限制在容器内 LockX: false, //是否锁定水平方向拖放 LockY: false, //是否锁定垂直方向拖放 Lock: false, //是否锁定 Transparent: false, //是否透明 onStart: function() {}, //开始移动时执行 onMove: function() {}, //移动时执行 onStop: function() {} //结束移动时执行 }; Extend(this.options, options || {}); }, //准备拖动 Start: function(oEvent) { if (this.Lock) { return; } this.Repair(); //记录鼠标相对拖放对象的位置 this._x = oEvent.clientX - this.Drag.offsetLeft; this._y = oEvent.clientY - this.Drag.offsetTop; //记录margin this._marginLeft = parseInt(CurrentStyle(this.Drag).marginLeft) || 0; this._marginTop = parseInt(CurrentStyle(this.Drag).marginTop) || 0; //mousemove时移动 mouseup时停止 addEventHandler(document, "mousemove", this._fM); addEventHandler(document, "mouseup", this._fS); if (isIE) { //焦点丢失 addEventHandler(this._Handle, "losecapture", this._fS); //设置鼠标捕获 this._Handle.setCapture(); } else { //焦点丢失 addEventHandler(window, "blur", this._fS); //阻止默认动作 oEvent.preventDefault(); }; //附加程序 this.onStart(); }, //修正范围 Repair: function() { if (this.Limit) { //修正错误范围参数 this.mxRight = Math.max(this.mxRight, this.mxLeft + this.Drag.offsetWidth); this.mxBottom = Math.max(this.mxBottom, this.mxTop + this.Drag.offsetHeight); //如果有容器必须设置position为relative或absolute来相对或绝对定位，并在获取offset之前设置 ! this._mxContainer || CurrentStyle(this._mxContainer).position == "relative" || CurrentStyle(this._mxContainer).position == "absolute" || (this._mxContainer.style.position = "relative"); } }, //拖动 Move: function(oEvent) { //判断是否锁定 if (this.Lock) { this.Stop(); return; }; //清除选择 window.getSelection ? window.getSelection().removeAllRanges() : document.selection.empty(); //设置移动参数 var iLeft = oEvent.clientX - this._x, iTop = oEvent.clientY - this._y; //设置范围限制 if (this.Limit) { //设置范围参数 var mxLeft = this.mxLeft, mxRight = this.mxRight, mxTop = this.mxTop, mxBottom = this.mxBottom; //如果设置了容器，再修正范围参数 if ( !! this._mxContainer) { mxLeft = Math.max(mxLeft, 0); mxTop = Math.max(mxTop, 0); mxRight = Math.min(mxRight, this._mxContainer.clientWidth); mxBottom = Math.min(mxBottom, this._mxContainer.clientHeight); }; //修正移动参数 iLeft = Math.max(Math.min(iLeft, mxRight - this.Drag.offsetWidth), mxLeft); iTop = Math.max(Math.min(iTop, mxBottom - this.Drag.offsetHeight), mxTop); } //设置位置，并修正margin if (!this.LockX) { this.Drag.style.left = iLeft - this._marginLeft + "px"; } if (!this.LockY) { this.Drag.style.top = iTop - this._marginTop + "px"; } //附加程序 this.onMove(); }, //停止拖动 Stop: function() { //移除事件 removeEventHandler(document, "mousemove", this._fM); removeEventHandler(document, "mouseup", this._fS); if (isIE) { removeEventHandler(this._Handle, "losecapture", this._fS); this._Handle.releaseCapture(); } else { removeEventHandler(window, "blur", this._fS); }; //附加程序 this.onStop(); } }; //以下是调用以上插件实现拖动 var drag = new Drag("idDrag", { mxContainer: "idContainer", Handle: "idHandle", Limit: true, onStart: function() { $("idShow").innerHTML = "开始拖放"; }, onMove: function() { $("idShow").innerHTML = "left：" + this.Drag.offsetLeft + "；top:" + this.Drag.offsetTop; }, onStop: function() { $("idShow").innerHTML = "结束拖放"; } }); $("idReset").onclick = function() { drag.Limit = true; drag.mxLeft = drag.mxTop = 0; drag.mxRight = drag.mxBottom = 9999; drag.LockX = drag.LockY = drag.Lock = false; } $("idLock").onclick = function() { drag.Lock = true; } $("idLockX").onclick = function() { drag.LockX = true; } $("idLockY").onclick = function() { drag.LockY = true; } $("idLimit").onclick = function() { drag.mxRight = drag.mxBottom = 200; drag.Limit = true; } $("idLimitOff").onclick = function() { drag.Limit = false; }</script> <!-- Generated by RunJS (Sun Mar 13 10:40:31 CST 2016) 0ms --></body></html>
效果：http://sandbox.runjs.cn/show/hbhrnv2g
1.2 简易拖放效果
<!DOCTYPE html> <!-- saved from url=(0037)http://sandbox.runjs.cn/show/xq0yj0sd --> <html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>简易拖放效果</title> </head> <body> <div id="central" style="position: absolute;"> 此拖动效果要将被拖动元素布局设为absolute </div> <style>#central { background-color:pink; width:300px; height:200px; }</style> <script>var isIE = (document.all) ? true: false; var $ = function(id) { return "string" == typeof id ? document.getElementById(id) : id; }; var Class = { create: function() { return function() { this.initialize.apply(this, arguments); } } } var Extend = function(destination, source) { for (var property in source) { destination[property] = source[property]; } } var Bind = function(object, fun) { return function() { return fun.apply(object, arguments); } } var BindAsEventListener = function(object, fun) { return function(event) { return fun.call(object, (event || window.event)); } } function addEventHandler(oTarget, sEventType, fnHandler) { if (oTarget.addEventListener) { oTarget.addEventListener(sEventType, fnHandler, false); } else if (oTarget.attachEvent) { oTarget.attachEvent("on" + sEventType, fnHandler); } else { oTarget["on" + sEventType] = fnHandler; } }; function removeEventHandler(oTarget, sEventType, fnHandler) { if (oTarget.removeEventListener) { oTarget.removeEventListener(sEventType, fnHandler, false); } else if (oTarget.detachEvent) { oTarget.detachEvent("on" + sEventType, fnHandler); } else { oTarget["on" + sEventType] = null; } }; //拖放程序 var SimpleDrag = Class.create(); SimpleDrag.prototype = { //拖放对象,触发对象 initialize: function(drag) { this.Drag = $(drag); this._x = this._y = 0; this._fM = BindAsEventListener(this, this.Move); this._fS = Bind(this, this.Stop); this.Drag.style.position = "absolute"; addEventHandler(this.Drag, "mousedown", BindAsEventListener(this, this.Start)); }, //准备拖动 Start: function(oEvent) { this._x = oEvent.clientX - this.Drag.offsetLeft; this._y = oEvent.clientY - this.Drag.offsetTop; addEventHandler(document, "mousemove", this._fM); addEventHandler(document, "mouseup", this._fS); }, //拖动 Move: function(oEvent) { this.Drag.style.left = oEvent.clientX - this._x + "px"; this.Drag.style.top = oEvent.clientY - this._y + "px"; }, //停止拖动 Stop: function() { removeEventHandler(document, "mousemove", this._fM); removeEventHandler(document, "mouseup", this._fS); } }; new SimpleDrag("central");</script> <!-- Generated by RunJS (Sun Mar 13 10:41:02 CST 2016) 0ms --></body></html>
效果：http://sandbox.runjs.cn/show/xq0yj0sd
实现2
<!DOCTYPE html> <!-- saved from url=(0037)http://sandbox.runjs.cn/show/o8sbts8t --> <html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"></head><body><html"> <title> D类 </title> <div id="block1_outer"> <div id="block1_inner" onmousedown="var wc = this;D.start(wc, null, function (property) { var node = wc.parentNode; var a = D.pos(node), b = D.pos(wc); node.style.left = property.left - b.x + a.x + 'px'; node.style.top = property.top - b.y + a.y + 'px'; }, null);"> 拽 </div> </div> <div id="block2_outer" onmousedown="var wc = this;D.start(wc, null, function (property) { wc.style.left = property.left + 'px'; wc.style.top = property.top + 'px'; }, null);"> 拽 </div> <style>html, body { margin:0; } #block1_outer { position:relative; width:100px; height:100px; background-color:#000000; } #block1_inner { position:absolute; width:20px; height:20px; line-height:20px; left:50%; top:50%; margin:-10px 0 0 -10px; background-color:#F00; text-align:center; cursor:move; } #block2_outer { width:50px; height:50px; line-height:50px; text-align:center; background-color:#F00; position:absolute; cursor:move; } #block2_inner { position:absolute; width:20px; height:20px; line-height:20px; left:50%; top:50%; margin:-10px 0 0 -10px; background-color:#F00; text-align:center; cursor:move; }</style> <script>//实现拖动的插件 !! window.__defineGetter__ && !/MSIE/.test(navigator.userAgent) && function() { ! window.opera && window.__defineGetter__('event', function() { //兼容Event对象 var o = arguments.callee; do { if (o.arguments[0] instanceof Event) return o.arguments[0]; } while ( o = o . caller ); return null; }); window.attachEvent = Document.prototype.attachEvent = Element.prototype.attachEvent = function(type, listener, capture) { //兼容attachEvent方法 return this.addEventListener(new String(type).substr(2), listener, capture || false); }; window.detachEvent = Document.prototype.detachEvent = Element.prototype.detachEvent = function(type, listener, capture) { //兼容detachEvent方法 return this.removeEventListener(new String(type).substr(2), listener, capture || false); }; } (); var D = { //拽补助类 lock: false , dom: function() { //document相关属性 return { left: document.documentElement.scrollLeft, top: document.documentElement.scrollTop, document.documentElement.clientWidth, height: document.documentElement.clientHeight, body: document.documentElement }; } , mos: function(e) { //获取鼠标绝对位置 var dom = this.dom(); return { 'x': dom.left + e.clientX, 'y': dom.top + e.clientY } } , pos: function(o) { //获取元素绝对位置 var x = 0, y = 0; do { x += o.offsetLeft, y += o.offsetTop; } while ( o = o . offsetParent ); return { 'x': x, 'y': y }; } , start: function(element, startEventHandler, moveEventHandler, stopEventHandler) { //移动开始 if (this.lock) return; else this.lock = true; //先上锁安全。。。:D var pos = this.pos(element) //元素位置 , mos = this.mos(window.event) //鼠标位置 , eventHandlers = { MF: null, EF: null } //事件记录 , property = { x: mos.x - pos.x, y: mos.y - pos.y, left: pos.x, top: pos.y } //属性 , _MF = this.move(moveEventHandler, property) //移动过程事件闭包 , _EF = this.stop(element, stopEventHandler, eventHandlers); //移动停止事件闭包 try { document.selection && document.selection.empty && (document.selection.empty(), 1) || window.getSelection && window.getSelection().removeAllRanges(); } catch(exp) {} document.attachEvent('onmousemove', _MF); //鼠标移动 document.attachEvent('onmouseup', _EF); //鼠标释放 element.setCapture ? (element.setCapture(), element.attachEvent('onlosecapture', _EF)) : window.attachEvent('onblur', _EF); //鼠标捕获丢失则释放 eventHandlers.MF = _MF, eventHandlers.EF = _EF; startEventHandler && startEventHandler(property); //直接传过去。。。请误污染- - } , move: function(moveEventHandler, property) { //移动中 var wc = this; return function(e) { var mos = wc.mos(e || window.event), dom = wc.dom(); window.getSelection && window.getSelection().removeAllRanges(); /MSIE/.test(navigator.userAgent) && function() { //IE滚屏 if (mos.x > dom.left + dom.width) dom.body.scrollLeft = mos.x - dom.width; else if (mos.x < dom.left) dom.body.scrollLeft = mos.x; if (mos.y > dom.top + dom.height) dom.body.scrollTop = mos.y - dom.height; else if (mos.y < dom.top) dom.body.scrollTop = mos.y; } (); property.left = mos.x - property.x, property.top = mos.y - property.y; moveEventHandler && moveEventHandler(property); //直接传过去。。。请误污染- -; }; } , stop: function(element, stopEventHandler, eventHandlers) { //移动结束 var wc = this; return function(e) { document.detachEvent('onmousemove', eventHandlers.MF); document.detachEvent('onmouseup', eventHandlers.EF); element.setCapture ? (element.detachEvent('onlosecapture', eventHandlers.EF), element.releaseCapture()) : window.detachEvent('onblur', eventHandlers.EF); wc.lock = false; //事件都干掉了可以放心解锁了 stopEventHandler && stopEventHandler(); }; } };</script> <!-- Generated by RunJS (Sun Mar 13 10:41:11 CST 2016) 1ms --></html"></body></html>