从网易扒过来的js调用广告显示文件(随机几率)

　　function column02(imgSource,url,chance,type) {

　　this.imgSource = imgSource;

　　this.url = url;

　　this.chance = chance;

　　this.type = type;

　　}

　　function dispColumn02() {

　　with (this)

　　switch (type){

　　case "img":

　　document.write("<A HREF=" + url + " target=_blank><IMG SRC=" + imgSource + " WIDTH=480 HEIGHT=250 BORDER=0></A>");

　　break;

　　case "html":

　　document.write("<IFRAME WIDTH=480 HEIGHT=250 MARGINWIDTH=0 MARGINHEIGHT=0 HSPACE=0 VSPACE=0 FRAMEBORDER=0 SCROLLING=no BORDERCOLOR=#000000 SRC="+ imgSource + "></iframe>");

　　break;

　　case "flash":

　　document.write("<embed src="+imgSource+" quality=high width=480 height=250 type=application/x-shockwave-flash pluginspage=http://www.macromedia.com/shockwave/download/index.cgi?P1_Prod_Version=ShockwaveFlash></embed>");

　　break;

　　default:

　　document.write("");

　　}

　　}

　　column02.prototype.dispColumn02 = dispColumn02;

　　columns02 = new Array();

　　// flash , html , img 代表三种不同的广告模式

　　// 200 之类的数目是设置出现的机率

　　columns02[0] = new column02("http://smsimg.163.com/honey/honey_ad.swf","",200,"flash");//主广告

　　columns02[1] = new column02("http://smsimg.163.com/honey/honey_photo.swf","",800,"flash"); //上传图片免月租

　　columns02[2] = new column02("http://smsimg.163.com/honey/honey_gold.swf","",800,"flash"); //登陆送金币

　　//columns02[] = new column02("f","",100,"");// （20030422～20030722）

　　sum_of_all_chances = 0;

　　for (i = 0; i < columns02.length; i++) {

　　sum_of_all_chances += columns02[i].chance;

　　}

　　function randomColumn02() {

　　chance_limit = 0;

　　randomly_selected_chance = Math.round((sum_of_all_chances - 1) * Math.random()) + 1;

　　for (i = 0; i < columns02.length; i++) {

　　chance_limit += columns02[i].chance;

　　if (randomly_selected_chance <= chance_limit) {

　　columns02[i].dispColumn02();

　　break;

　　}

　　}

　　}

　　this_column02 = randomColumn02();