js读写Cookie

String.prototype.trim = function String$trim() {
    if (arguments.length !== 0) throw Error.parameterCount();
    return this.replace(/^\s+|\s+$/g,'');
}

CookieUtil = function(){};

CookieUtil.readCookie = function(name){
    var cookies = document.cookie.split(";");
    var len = cookies.length;
    var value = "";
    var searchStr = name+"=";
    for(var i = 0; i < len ; i ++){
        var str = cookies[i].trim();
        var index = str.indexOf("=");
        if(str.indexOf(searchStr) != -1){
            value= str.substring(index+1);
            break;
        }
    }
    return encodeURIComponent(value);
}

CookieUtil.setCookie = function(name,value,options){
  var expires = '';
  alert(options.expires ?true:false);
  if( options.expires && (typeof options.expires == 'number' || options.expires.toUTCString())){
    var date;
    if(typeof options.expires == 'number'){
        date = new Date();
        date.setTime((date.getTime()+expires*24*60*60*1000));
    }else{
        date = options.expires;
    }
    expires = "; expires="+date.toUTCString();
  }
  var domain = options.domain?"; domain="+options.domain:"";
  var path = options.path ? "; path="+options.path:'';
  var secure = options.secure ? ": secure="+options.secure:"";
  document.cookie = [name,'=',value,domain,path,secure].join('');
}