写了一个定时器类，以方便应用

/**
 *  执行计划任务 author：littlehow
 *   2015-04-25
 *  @param time     --执行时间间隔或者滞后时间
 *  @param fname    --函数名称
 *  @param loopflag --循环次数 -1代表无限循环 0代表不循环(即timeout) 其余正数代表循环次数
*/
function Timer(time, fname, loop){
if(this instanceof Timer){
this.id = -1;
this.time = time;
this.fname = fname;
this.stopFlag = false;
this.loop = this.count = this.currentCount = 0;
if(typeof loop=="number"){
this.loop = this.count = loop;
}
this.myFun = function(obj){
return function(){
if(--obj.count<=0){
obj.stop();
}
obj.currentCount++;
obj.fname();
};
};

this.newFun = function(obj){
return function(){
obj.currentCount++;
obj.fname();
};
};

this.start = function(){
this.currentCount = 0;
this.stopFlag = false;
if(this.loop==-1){
this.id = window.setInterval(this.newFun(this),this.time);
}else if(this.loop==0){
this.id = window.setTimeout(this.fname, this.time);
}else{
this.id = window.setInterval(this.myFun(this), this.time);
}
};
this.stop = function(){
if(this.stopFlag){
return;
}else{
this.stopFlag = true;
}
if(this.loop==0){
window.clearTimeout(this.id);
}else{
window.clearInterval(this.id);
}
};
this.setTime = function(time){
this.time = time;
};
this.setLoop = function(loop){
this.loop = loop;
};
this.setFname = function(fname){
this.fname = fname;
};
this.getId = function(){
return this.id;
};
}else{
return new Timer(time, fname, loopflag);
}
};