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 setCookie(c_name,value,expiredays,ckyu){
  var ick='';
  ick=c_name+ '=' +escape(value) + ';';
  if(ckyu==null) ckyu='allsite';
  if(ckyu!='currpath') ick=ick + 'path=/;';
  if(expiredays!=null){
    var exdate=new Date();
    exdate.setDate(exdate.getDate()+expiredays);
    ick=ick + 'expires='+exdate.toGMTString() + ';';
  }
  if(ick!='') document.cookie=ick;
}

function delCookie(cn){//ɾ³ýcookie
setCookie(cn,'',-1)
return;
  var exp = new Date();
  exp.setTime(exp.getTime() - 1);
  var cval=getCookie(cn);
  document.write('|'+cval+'|')
  if(cval!='') document.cookie= cn + "="+cval+";expires="+exp.toGMTString();
}