JavaScript 颜色梯度和渐变效果

var ColorTrans = function(obj, options){

this._obj = $(obj);
this._timer = null;//定时器
this._index = 0;//索引
this._colors = [];//颜色集合
this._grads = new ColorGrads();

this.SetOptions(options);

this.Speed = Math.abs(this.options.Speed);
this.CssColor = this.options.CssColor;

this._startColor = this.options.StartColor || CurrentStyle(this._obj)[this.CssColor];
this._endColor = this.options.EndColor;
this._step = Math.abs(this.options.Step);

this.Reset();
this.SetColor();
};
ColorTrans.prototype = {
//设置默认属性
SetOptions: function(options) {
this.options = {//默认值
StartColor: "",//开始颜色
EndColor: "#000",//结束颜色
Step: 20,//渐变级数
Speed: 20,//渐变速度
CssColor: "color"//设置属性（Scripting属性）
};
Extend(this.options, options || {});
},
//重设颜色集合
Reset: function(color) {
//修改颜色后必须重新获取颜色集合
color = Extend({ StartColor: this._startColor, EndColor: this._endColor, Step: this._step }, color || {});
//设置属性
this._grads.StartColor = this._startColor = color.StartColor;
this._grads.EndColor = this._endColor = color.EndColor;
this._grads.Step = this._step = color.Step;
//获取颜色集合
this._colors = this._grads.Create();
this._index = 0;
},
//颜色渐入
FadeIn: function() {
this.Stop(); this._index++; this.SetColor();
if(this._index < this._colors.length - 1){
this._timer = setTimeout(Bind(this, this.FadeIn), this.Speed);
}
},
//颜色渐出
FadeOut: function() {
this.Stop(); this._index--; this.SetColor();
if(this._index > 0){
this._timer = setTimeout(Bind(this, this.FadeOut), this.Speed);
}
},
//颜色设置
SetColor: function() {
var color = this._colors[Math.min(Math.max(0, this._index), this._colors.length - 1)];
this._obj.style[this.CssColor] = "rgb(" + color[0] + "," + color[1] + "," + color[2] + ")";
},
//停止
Stop: function() {
clearTimeout(this._timer);
}
};