JavaScript教程:图片切割效果(4)
这里贴出切割效果部分的代码：
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) {
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;
}
};
//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() {
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 }
}
}