问javascript:检测是否启用了XP或经典windows主题

EN

function isXpTheme() {
  var rgb;
  var map = { "rgb(212,208,200)" : false,
              "rgb(236,233,216)" : true };
  var $elem = $("<button>");
  $elem.css("backgroundColor", "ButtonFace");
  $("body").append($elem);
  var elem = $elem.get(0);
  if (document.defaultView && document.defaultView.getComputedStyle) {
    s = document.defaultView.getComputedStyle(elem, "");
    rgb = s && s.getPropertyValue("background-color");
  } else if (elem.currentStyle) {
    rgb = (function (el) { // get a rgb based color on IE
    var oRG =document.body.createTextRange();
    oRG.moveToElementText(el);
    var iClr=oRG.queryCommandValue("BackColor");
      return "rgb("+(iClr & 0xFF)+","+((iClr & 0xFF00)>>8)+","+
                  ((iClr & 0xFF0000)>>16)+")";
    })(elem);
  } else if (elem.style["backgroundColor"]) {
    rgb = elem.style["backgroundColor"];
  } else  {
    rgb = null;
  }
  $elem.remove();
  rgb = rgb.replace(/[ ]+/g,"")
  if(rgb){;
    return map[rgb];
  }
}