//获取url的参数
function GetQueryString(name) {
   var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)","i");
   var r = window.location.search.substr(1).match(reg);
   if (r!=null) return unescape(r[2]); return null;
}
//设置cookie
function setCookie(c_name,value,expiredays)
{
var exdate=new Date()
exdate.setDate(exdate.getDate()+expiredays)
document.cookie=c_name+ "=" +escape(value)+
((expiredays==null) ? "" : ";expires="+exdate.toGMTString())
}
//获取cookie
function getCookie(c_name)
{
if (document.cookie.length>0)
  {
  c_start=document.cookie.indexOf(c_name + "=")
  if (c_start!=-1)
    { 
    c_start=c_start + c_name.length+1 
    c_end=document.cookie.indexOf(";",c_start)
    if (c_end==-1) c_end=document.cookie.length
    return unescape(document.cookie.substring(c_start,c_end))
    } 
  }
return ""
}
function getHost(url) {
        var host = "null";
        if(typeof url == "undefined"
                        || null == url)
                url = window.location.href;
        var regex = /.*\:\/\/([^\/]*).*/;
        var match = url.match(regex);
        if(typeof match != "undefined"
                        && null != match)
                host = match[1];
        return host;
}