JS获取一个未知DIV高度的方法

var height = element.clientHeight;

getDimensions: function(element) {
  element = $(element);
  var display = $(element).getStyle('display');
  if (display != 'none' && display != null) // Safari bug
   return {width: element.offsetWidth, height: element.offsetHeight};
  // All *Width and *Height properties give 0 on elements with display none,
  // so enable the element temporarily
  var els = element.style;
  var originalVisibility = els.visibility;
  var originalPosition = els.position;
  var originalDisplay = els.display;
  els.visibility = 'hidden';
  els.position = 'absolute';
  els.display = 'block';
  var originalWidth = element.clientWidth;
  var originalHeight = element.clientHeight;
  els.display = originalDisplay;
  els.position = originalPosition;
  els.visibility = originalVisibility;
  return {width: originalWidth, height: originalHeight};
}