function changeScheme(color) {
	document.body.className = color;
	addCookie("pagecolor",color,24*365);
}
function loadScheme() {
	//alert(document.cookie);
    var pagecolor = getCookie("pagecolor");
	if(pagecolor!=null){
		document.body.className = pagecolor;
	}else{
		document.body.className = "scheme-blue";
	}
 
}

function addCookie(objName,objValue,objHours){//添加cookie
   var str = objName + "=" + escape(objValue);
   if(objHours > 0){//为0时不设定过期时间，浏览器关闭时cookie自动消失
    var date = new Date();
    var ms = objHours*3600*1000;
    date.setTime(date.getTime() + ms);
    str += "; expires=" + date.toGMTString();
   }
   document.cookie = str;
   //alert("添加cookie成功");
  }
  
  function getCookie(objName){//获取指定名称的cookie的值
   var arrStr = document.cookie.split("; ");
   for(var i = 0;i < arrStr.length;i ++){
    var temp = arrStr[i].split("=");
    if(temp[0] == objName) return unescape(temp[1]);
   } 
  }
  
  function delCookie(name){//为了删除指定名称的cookie，可以将其过期时间设定为一个过去的时间
   var date = new Date();
   date.setTime(date.getTime() - 10000);
   document.cookie = name + "=a; expires=" + date.toGMTString();
  }