首先要准备4个js文件：
1）prototype.js
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) {
var args = Array.prototype.slice.call(arguments).slice(2); return function(event) { return fun.apply(object, [event || window.event].concat(args)); }}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; }};2）ImgCropper.js
//图片切割
var ImgCropper = Class.create();ImgCropper.prototype = { //容器对象,控制层,图片地址 initialize: function(container, handle, url, options) { this._Container = $(container); //容器对象 this._layHandle = $(handle); //控制层 this.Url = url; //图片地址this._layBase = this._Container.appendChild(document.createElement("img")); //底层
this._layCropper = this._Container.appendChild(document.createElement("img")); //切割层 this._layCropper.onload = Bind(this, this.SetPos); //用来设置大小 this._tempImg = document.createElement("img"); this._tempImg.onload = Bind(this, this.SetSize);this.SetOptions(options);
this.Opacity = Math.round(this.options.Opacity);
this.Color = this.options.Color; this.Scale = !!this.options.Scale; this.Ratio = Math.max(this.options.Ratio, 0); this.Width = Math.round(this.options.Width); this.Height = Math.round(this.options.Height);//设置预览对象
var oPreview = $(this.options.Preview); //预览对象 if (oPreview) { oPreview.style.position = "relative"; oPreview.style.overflow = "hidden"; this.viewWidth = Math.round(this.options.viewWidth); this.viewHeight = Math.round(this.options.viewHeight); //预览图片对象 this._view = oPreview.appendChild(document.createElement("img")); this._view.style.position = "absolute"; this._view.onload = Bind(this, this.SetPreview); } //设置拖放 this._drag = new Drag(this._layHandle, { Limit: true, onMove: Bind(this, this.SetPos), Transparent: true }); //设置缩放 this.Resize = !!this.options.Resize; if (this.Resize) { var op = this.options, _resize = new Resize(this._layHandle, { Max: true, onResize: Bind(this, this.SetPos) }); //设置缩放触发对象 op.RightDown && (_resize.Set(op.RightDown, "right-down")); op.LeftDown && (_resize.Set(op.LeftDown, "left-down")); op.RightUp && (_resize.Set(op.RightUp, "right-up")); op.LeftUp && (_resize.Set(op.LeftUp, "left-up")); op.Right && (_resize.Set(op.Right, "right")); op.Left && (_resize.Set(op.Left, "left")); op.Down && (_resize.Set(op.Down, "down")); op.Up && (_resize.Set(op.Up, "up")); //最小范围限制 this.Min = !!this.options.Min; this.minWidth = Math.round(this.options.minWidth); this.minHeight = Math.round(this.options.minHeight); //设置缩放对象 this._resize = _resize; } //设置样式 this._Container.style.position = "relative"; this._Container.style.overflow = "hidden"; this._layHandle.style.zIndex = 200; this._layCropper.style.zIndex = 100; this._layBase.style.position = this._layCropper.style.position = "absolute"; this._layBase.style.top = this._layBase.style.left = this._layCropper.style.top = this._layCropper.style.left = 0; //对齐 //初始化设置 this.Init(); }, //设置默认属性 SetOptions: function(options) { this.options = { //默认值 Opacity: 50, //透明度(0到100) Color: "", //背景色 Width: 0, //图片高度 Height: 0, //图片高度 //缩放触发对象 Resize: false, //是否设置缩放 Right: "", //右边缩放对象 Left: "", //左边缩放对象 Up: "", //上边缩放对象 Down: "", //下边缩放对象 RightDown: "", //右下缩放对象 LeftDown: "", //左下缩放对象 RightUp: "", //右上缩放对象 LeftUp: "", //左上缩放对象 Min: false, //是否最小宽高限制(为true时下面min参数有用) minWidth: 50, //最小宽度 minHeight: 50, //最小高度 Scale: false, //是否按比例缩放 Ratio: 0, //缩放比例(宽/高) //预览对象设置 Preview: "", //预览对象 viewWidth: 0, //预览宽度 viewHeight: 0//预览高度 }; Extend(this.options, options || {}); }, //初始化对象 Init: function() { //设置背景色 this.Color && (this._Container.style.backgroundColor = this.Color); //设置图片 this._tempImg.src = this._layBase.src = this._layCropper.src = this.Url; //设置透明 if (isIE) { this._layBase.style.filter = "alpha(opacity:" + this.Opacity + ")"; } else { this._layBase.style.opacity = this.Opacity / 100; } //设置预览对象 this._view && (this._view.src = this.Url); //设置缩放 if (this.Resize) { with (this._resize) { Scale = this.Scale; Ratio = this.Ratio; Min = this.Min; minWidth = this.minWidth; minHeight = this.minHeight; } } }, //设置切割样式 SetPos: function() { //ie6渲染bug if (isIE6) { with (this._layHandle.style) { zoom = .9; zoom = 1; }; }; //获取位置参数 var p = this.GetPos(); //按拖放对象的参数进行切割 this._layCropper.style.clip = "rect(" + p.Top + "px " + (p.Left + p.Width) + "px " + (p.Top + p.Height) + "px " + p.Left + "px)"; //设置预览 this.SetPreview(); }, //设置预览效果 SetPreview: function() { if (this._view) { //预览显示的宽和高 var p = this.GetPos(), s = this.GetSize(p.Width, p.Height, this.viewWidth, this.viewHeight), scale = s.Height / p.Height; //按比例设置参数 var pHeight = this._layBase.height * scale, pWidth = this._layBase.width * scale, pTop = p.Top * scale, pLeft = p.Left * scale; //设置预览对象 with (this._view.style) { //设置样式 width = pWidth + "px"; height = pHeight + "px"; top = -pTop + "px "; left = -pLeft + "px"; //切割预览图 clip = "rect(" + pTop + "px " + (pLeft + s.Width) + "px " + (pTop + s.Height) + "px " + pLeft + "px)"; } } }, //设置图片大小 SetSize: function() { var s = this.GetSize(this._tempImg.width, this._tempImg.height, this.Width, this.Height); //设置底图和切割图 this._layBase.style.width = this._layCropper.style.width = s.Width + "px"; this._layBase.style.height = this._layCropper.style.height = s.Height + "px"; //设置拖放范围 this._drag.mxRight = s.Width; this._drag.mxBottom = s.Height; //设置缩放范围 if (this.Resize) { this._resize.mxRight = s.Width; this._resize.mxBottom = s.Height; } }, //获取当前样式 GetPos: function() { with (this._layHandle) { return { Top: offsetTop, Left: offsetLeft, Width: offsetWidth, Height: offsetHeight } } }, //获取尺寸 GetSize: function(nowWidth, nowHeight, fixWidth, fixHeight) { var iWidth = nowWidth, iHeight = nowHeight, scale = iWidth / iHeight; //按比例设置 if (fixHeight) { iWidth = (iHeight = fixHeight) * scale; } if (fixWidth && (!fixHeight || iWidth > fixWidth)) { iHeight = (iWidth = fixWidth) / scale; } //返回尺寸对象 return { Width: iWidth, Height: iHeight } }}3)Drag.js
//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(); }};4)Resize.js
//缩放程序
var Resize = Class.create();Resize.prototype = { //缩放对象 initialize: function(obj, options) { this._obj = $(obj); //缩放对象 this._styleWidth = this._styleHeight = this._styleLeft = this._styleTop = 0; //样式参数 this._sideRight = this._sideDown = this._sideLeft = this._sideUp = 0; //坐标参数 this._fixLeft = this._fixTop = 0; //定位参数 this._scaleLeft = this._scaleTop = 0; //定位坐标 this._mxSet = function(){}; //范围设置程序 this._mxRightWidth = this._mxDownHeight = this._mxUpHeight = this._mxLeftWidth = 0; //范围参数 this._mxScaleWidth = this._mxScaleHeight = 0; //比例范围参数 this._fun = function(){}; //缩放执行程序 //获取边框宽度 var _style = CurrentStyle(this._obj); this._borderX = (parseInt(_style.borderLeftWidth) || 0) + (parseInt(_style.borderRightWidth) || 0); this._borderY = (parseInt(_style.borderTopWidth) || 0) + (parseInt(_style.borderBottomWidth) || 0); //事件对象(用于绑定移除事件) this._fR = BindAsEventListener(this, this.Resize); this._fS = Bind(this, this.Stop); this.SetOptions(options); //范围限制 this.Max = !!this.options.Max; this._mxContainer = $(this.options.mxContainer) || null; this.mxLeft = Math.round(this.options.mxLeft); this.mxRight = Math.round(this.options.mxRight); this.mxTop = Math.round(this.options.mxTop); this.mxBottom = Math.round(this.options.mxBottom); //宽高限制 this.Min = !!this.options.Min; this.minWidth = Math.round(this.options.minWidth); this.minHeight = Math.round(this.options.minHeight); //按比例缩放 this.Scale = !!this.options.Scale; this.Ratio = Math.max(this.options.Ratio, 0); this.onResize = this.options.onResize; this._obj.style.position = "absolute"; !this._mxContainer || CurrentStyle(this._mxContainer).position == "relative" || (this._mxContainer.style.position = "relative"); }, //设置默认属性 SetOptions: function(options) { this.options = { //默认值 Max: false, //是否设置范围限制(为true时下面mx参数有用) mxContainer:"", //指定限制在容器内 mxLeft: 0, //左边限制 mxRight: 9999, //右边限制 mxTop: 0, //上边限制 mxBottom: 9999, //下边限制 Min: false, //是否最小宽高限制(为true时下面min参数有用) minWidth: 50, //最小宽度 minHeight: 50, //最小高度 Scale: false, //是否按比例缩放 Ratio: 0, //缩放比例(宽/高) onResize: function(){} //缩放时执行 }; Extend(this.options, options || {}); }, //设置触发对象 Set: function(resize, side) { var resize = $(resize), fun; if(!resize) return; //根据方向设置 switch (side.toLowerCase()) { case "up" : fun = this.Up; break; case "down" : fun = this.Down; break; case "left" : fun = this.Left; break; case "right" : fun = this.Right; break; case "left-up" : fun = this.LeftUp; break; case "right-up" : fun = this.RightUp; break; case "left-down" : fun = this.LeftDown; break; case "right-down" : default : fun = this.RightDown; }; //设置触发对象 addEventHandler(resize, "mousedown", BindAsEventListener(this, this.Start, fun)); }, //准备缩放 Start: function(e, fun, touch) { //防止冒泡(跟拖放配合时设置) e.stopPropagation ? e.stopPropagation() : (e.cancelBubble = true); //设置执行程序 this._fun = fun; //样式参数值 this._styleWidth = this._obj.clientWidth; this._styleHeight = this._obj.clientHeight; this._styleLeft = this._obj.offsetLeft; this._styleTop = this._obj.offsetTop; //四条边定位坐标 this._sideLeft = e.clientX - this._styleWidth; this._sideRight = e.clientX + this._styleWidth; this._sideUp = e.clientY - this._styleHeight; this._sideDown = e.clientY + this._styleHeight; //top和left定位参数 this._fixLeft = this._styleLeft + this._styleWidth; this._fixTop = this._styleTop + this._styleHeight; //缩放比例 if(this.Scale){ //设置比例 this.Ratio = Math.max(this.Ratio, 0) || this._styleWidth / this._styleHeight; //left和top的定位坐标 this._scaleLeft = this._styleLeft + this._styleWidth / 2; this._scaleTop = this._styleTop + this._styleHeight / 2; }; //范围限制 if(this.Max){ //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); }; //根据最小值再修正 mxRight = Math.max(mxRight, mxLeft + (this.Min ? this.minWidth : 0) + this._borderX); mxBottom = Math.max(mxBottom, mxTop + (this.Min ? this.minHeight : 0) + this._borderY); //由于转向时要重新设置所以写成function形式 this._mxSet = function(){ this._mxRightWidth = mxRight - this._styleLeft - this._borderX; this._mxDownHeight = mxBottom - this._styleTop - this._borderY; this._mxUpHeight = Math.max(this._fixTop - mxTop, this.Min ? this.minHeight : 0); this._mxLeftWidth = Math.max(this._fixLeft - mxLeft, this.Min ? this.minWidth : 0); }; this._mxSet(); //有缩放比例下的范围限制 if(this.Scale){ this._mxScaleWidth = Math.min(this._scaleLeft - mxLeft, mxRight - this._scaleLeft - this._borderX) * 2; this._mxScaleHeight = Math.min(this._scaleTop - mxTop, mxBottom - this._scaleTop - this._borderY) * 2; }; }; //mousemove时缩放 mouseup时停止 addEventHandler(document, "mousemove", this._fR); addEventHandler(document, "mouseup", this._fS); if(isIE){ addEventHandler(this._obj, "losecapture", this._fS); this._obj.setCapture(); }else{ addEventHandler(window, "blur", this._fS); e.preventDefault(); }; }, //缩放 Resize: function(e) { //清除选择 window.getSelection ? window.getSelection().removeAllRanges() : document.selection.empty(); //执行缩放程序 this._fun(e); //设置样式，变量必须大于等于0否则ie出错 with(this._obj.style){ width = this._styleWidth + "px"; height = this._styleHeight + "px"; top = this._styleTop + "px"; left = this._styleLeft + "px"; } //附加程序 this.onResize(); }, //缩放程序 //上 Up: function(e) { this.RepairY(this._sideDown - e.clientY, this._mxUpHeight); this.RepairTop(); this.TurnDown(this.Down); }, //下 Down: function(e) { this.RepairY(e.clientY - this._sideUp, this._mxDownHeight); this.TurnUp(this.Up); }, //右 Right: function(e) { this.RepairX(e.clientX - this._sideLeft, this._mxRightWidth); this.TurnLeft(this.Left); }, //左 Left: function(e) { this.RepairX(this._sideRight - e.clientX, this._mxLeftWidth); this.RepairLeft(); this.TurnRight(this.Right); }, //右下 RightDown: function(e) { this.RepairAngle( e.clientX - this._sideLeft, this._mxRightWidth, e.clientY - this._sideUp, this._mxDownHeight ); this.TurnLeft(this.LeftDown) || this.Scale || this.TurnUp(this.RightUp); }, //右上 RightUp: function(e) { this.RepairAngle( e.clientX - this._sideLeft, this._mxRightWidth, this._sideDown - e.clientY, this._mxUpHeight ); this.RepairTop(); this.TurnLeft(this.LeftUp) || this.Scale || this.TurnDown(this.RightDown); }, //左下 LeftDown: function(e) { this.RepairAngle( this._sideRight - e.clientX, this._mxLeftWidth, e.clientY - this._sideUp, this._mxDownHeight ); this.RepairLeft(); this.TurnRight(this.RightDown) || this.Scale || this.TurnUp(this.LeftUp); }, //左上 LeftUp: function(e) { this.RepairAngle( this._sideRight - e.clientX, this._mxLeftWidth, this._sideDown - e.clientY, this._mxUpHeight ); this.RepairTop(); this.RepairLeft(); this.TurnRight(this.RightUp) || this.Scale || this.TurnDown(this.LeftDown); }, //修正程序 //水平方向 RepairX: function(iWidth, mxWidth) { iWidth = this.RepairWidth(iWidth, mxWidth); if(this.Scale){ var iHeight = this.RepairScaleHeight(iWidth); if(this.Max && iHeight > this._mxScaleHeight){ iHeight = this._mxScaleHeight; iWidth = this.RepairScaleWidth(iHeight); }else if(this.Min && iHeight < this.minHeight){ var tWidth = this.RepairScaleWidth(this.minHeight); if(tWidth < mxWidth){ iHeight = this.minHeight; iWidth = tWidth; } } this._styleHeight = iHeight; this._styleTop = this._scaleTop - iHeight / 2; } this._styleWidth = iWidth; }, //垂直方向 RepairY: function(iHeight, mxHeight) { iHeight = this.RepairHeight(iHeight, mxHeight); if(this.Scale){ var iWidth = this.RepairScaleWidth(iHeight); if(this.Max && iWidth > this._mxScaleWidth){ iWidth = this._mxScaleWidth; iHeight = this.RepairScaleHeight(iWidth); }else if(this.Min && iWidth < this.minWidth){ var tHeight = this.RepairScaleHeight(this.minWidth); if(tHeight < mxHeight){ iWidth = this.minWidth; iHeight = tHeight; } } this._styleWidth = iWidth; this._styleLeft = this._scaleLeft - iWidth / 2; } this._styleHeight = iHeight; }, //对角方向 RepairAngle: function(iWidth, mxWidth, iHeight, mxHeight) { iWidth = this.RepairWidth(iWidth, mxWidth); if(this.Scale){ iHeight = this.RepairScaleHeight(iWidth); if(this.Max && iHeight > mxHeight){ iHeight = mxHeight; iWidth = this.RepairScaleWidth(iHeight); }else if(this.Min && iHeight < this.minHeight){ var tWidth = this.RepairScaleWidth(this.minHeight); if(tWidth < mxWidth){ iHeight = this.minHeight; iWidth = tWidth; } } }else{ iHeight = this.RepairHeight(iHeight, mxHeight); } this._styleWidth = iWidth; this._styleHeight = iHeight; }, //top RepairTop: function() { this._styleTop = this._fixTop - this._styleHeight; }, //left RepairLeft: function() { this._styleLeft = this._fixLeft - this._styleWidth; }, //height RepairHeight: function(iHeight, mxHeight) { iHeight = Math.min(this.Max ? mxHeight : iHeight, iHeight); iHeight = Math.max(this.Min ? this.minHeight : iHeight, iHeight, 0); return iHeight; }, //width RepairWidth: function(iWidth, mxWidth) { iWidth = Math.min(this.Max ? mxWidth : iWidth, iWidth); iWidth = Math.max(this.Min ? this.minWidth : iWidth, iWidth, 0); return iWidth; }, //比例高度 RepairScaleHeight: function(iWidth) { return Math.max(Math.round((iWidth + this._borderX) / this.Ratio - this._borderY), 0); }, //比例宽度 RepairScaleWidth: function(iHeight) { return Math.max(Math.round((iHeight + this._borderY) * this.Ratio - this._borderX), 0); }, //转向程序 //转右 TurnRight: function(fun) { if(!(this.Min || this._styleWidth)){ this._fun = fun; this._sideLeft = this._sideRight; this.Max && this._mxSet(); return true; } }, //转左 TurnLeft: function(fun) { if(!(this.Min || this._styleWidth)){ this._fun = fun; this._sideRight = this._sideLeft; this._fixLeft = this._styleLeft; this.Max && this._mxSet(); return true; } }, //转上 TurnUp: function(fun) { if(!(this.Min || this._styleHeight)){ this._fun = fun; this._sideDown = this._sideUp; this._fixTop = this._styleTop; this.Max && this._mxSet(); return true; } }, //转下 TurnDown: function(fun) { if(!(this.Min || this._styleHeight)){ this._fun = fun; this._sideUp = this._sideDown; this.Max && this._mxSet(); return true; } }, //停止缩放 Stop: function() { removeEventHandler(document, "mousemove", this._fR); removeEventHandler(document, "mouseup", this._fS); if(isIE){ removeEventHandler(this._obj, "losecapture", this._fS); this._obj.releaseCapture(); }else{ removeEventHandler(window, "blur", this._fS); } }};然后写一个处理程序，用来画出截图：
ImageCropper.ashx
<%@ WebHandler Language="c#" Class="ImageCropper" Debug="true" %>
using System;using System.Web;using System.Drawing;using System.IO;public class ImageCropper : IHttpHandler
{#region IHttpHandler 成员
public void ProcessRequest(HttpContext context) { string ImgPath = Convert.ToString(context.Request["p"]); int PointX = Convert.ToInt32(context.Request["x"]); int PointY = Convert.ToInt32(context.Request["y"]); int CutWidth = Convert.ToInt32(context.Request["w"]); int CutHeight = Convert.ToInt32(context.Request["h"]); int PicWidth = Convert.ToInt32(context.Request["pw"]); int PicHeight = Convert.ToInt32(context.Request["ph"]);context.Response.ContentType = "image/jpeg";
ShowImage(HttpContext.Current.Server.MapPath(ImgPath), PointX, PointY, CutWidth, CutHeight, PicWidth, PicHeight).WriteTo(context.Response.OutputStream); }private MemoryStream ShowImage(string path, int PointX, int PointY, int CutWidth, int CutHeight, int PicWidth, int PicHeight)
{ Image image = Image.FromFile(path); Bitmap bm = new Bitmap(CutWidth, CutHeight, System.Drawing.Imaging.PixelFormat.Format24bppRgb); Graphics graphics = Graphics.FromImage(bm); graphics.DrawImage(image, new Rectangle(0, 0, CutWidth, CutHeight), PointX * image.Width / PicWidth, PointY * image.Height / PicHeight, CutWidth * image.Width / PicWidth, CutHeight * image.Height / PicHeight, GraphicsUnit.Pixel); int a = path.LastIndexOf('.'); int b = path.LastIndexOf('\\'); string _newPic = path.Substring(0, b) + "\\new_" + DateTime.Now.ToFileTimeUtc().ToString("X") + ".jpg"; bm.Save(_newPic, System.Drawing.Imaging.ImageFormat.Jpeg); MemoryStream ms = new MemoryStream(); bm.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg); image.Dispose(); graphics.Dispose(); bm.Dispose(); return ms; } public bool IsReusable { get { return false; } } #endregion}最后是页面代码：
ImageCropper.htm
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"><head> <title></title><script language="javascript" type="text/javascript" src="js/prototype.js"></script>
<script language="javascript" type="text/javascript" src="js/ImgCropper.js"></script>
<script language="javascript" type="text/javascript" src="js/Drag.js"></script>
<script language="javascript" type="text/javascript" src="js/Resize.js"></script>
<style type="text/css">
#ViewDiv { width: 200px; height: 200px; } #bgDiv { width: 500px; height: 600px; position: relative; } #dragDiv { width: 100px; height: 80px; left: 50px; top: 50px; border: solid 1px #fff; cursor: move; } #dRightDown, #dLeftDown, #dLeftUp, #dRightUp, #dRight, #dLeft, #dUp, #dDown { position: absolute; background: #FFF; border: 1px solid #333; width: 6px; height: 6px; z-index: 500; font-size: 0; opacity: 0.5; filter: alpha(opacity=50); } #dLeftDown, #dRightUp { cursor: ne-resize; } #dRightDown, #dLeftUp { cursor: nw-resize; } #dRight, #dLeft { cursor: e-resize; } #dUp, #dDown { cursor: n-resize; } #dLeftDown { left: 0px; bottom: 0px; } #dRightUp { right: 0px; top: 0px; } #dRightDown { right: 0px; bottom: 0px; background-color: #00F; } #dLeftUp { left: 0px; top: 0px; } #dRight { right: 0px; top: 50%; margin-top: -4px; } #dLeft { left: 0px; top: 50%; margin-top: -4px; } #dUp { top: 0px; left: 50%; margin-left: -4px; } #dDown { bottom: 0px; left: 50%; margin-left: -4px; } </style></head><body> <div id="bgDiv"> <div id="dragDiv"> <div id="dRightDown"> </div> <div id="dLeftDown"> </div> <div id="dRightUp"> </div> <div id="dLeftUp"> </div> <div id="dRight"> </div> <div id="dLeft"> </div> <div id="dDown"> </div> <div id="dUp"> </div> </div> </div> <div id="ViewDiv"> </div> <br /> <br /> <input type="button" value="生成图片" οnclick="create();" /><br /> <br /> <img id="ShowImg" alt="" src="" style="display: none;" /><script language="javascript" type="text/javascript">
var isIE = (document.all) ? true : false; // 是否ie var isIE6 = isIE && ([/MSIE (\d)\.0/i.exec(navigator.userAgent)][0][1] == 6); var $ = function(id) { //返回id对象 return "string" == typeof id ? document.getElementById(id) : id; }; var imgCropper = new ImgCropper("bgDiv", "dragDiv", "image/Hydrangeas.jpg", { Width: 500, Height: 600, Color: "#FFF", Resize: true, Right: "dRight", Left: "dLeft", Up: "dUp", Down: "dDown", RightDown: "dRightDown", LeftDown: "dLeftDown", RightUp: "dRightUp", LeftUp: "dLeftUp", Preview: "ViewDiv"// viewWidth: 200, //这里要是不写的话预览截图就等同大// viewHeight: 200 }) function create() { var path = imgCropper.Url; var o = imgCropper.GetPos(); x = o.Left; y = o.Top; w = o.Width; h = o.Height; pw = imgCropper._layBase.width; ph = imgCropper._layBase.height; $("ShowImg").onload = function() { this.style.display = ""; } $("ShowImg").src = "ImageCropper.ashx?p=" + path + "&x=" + x + "&y=" + y + "&w=" + w + "&h=" + h + "&pw=" + pw + "&ph=" + ph + "&" + Math.random(); } </script></body>
</html>望指点