function outlook()
{
this.titlelist=new Array();
this.itemlist=new Array();
this.divstyle="style='height:100%;width:100%;overflow:auto' align=center";
this.otherclass="border=0 cellspacing='0' cellpadding='0' style='height:100%;width:100%'valign=middle align=center ";
this.addtitle=addtitle;
this.additem=additem;
this.starttitle=-1;
this.show=show;
this.getOutLine=getOutLine;
this.opentitle=this.starttitle;
this.reflesh=outreflesh;
this.timedelay=50;
this.inc=10;

}
这一段JS是实现什么功能的呢