text: jQuery.fn.extend({
    autoHeight: function () {
      return this.each(function () {
        var $this = jQuery(this);
        if (!$this.attr("_initAdjustHeight")) {
          $this.attr("_initAdjustHeight", $this.outerHeight());
        }
        _adjustH(this).on("input", function () {
          _adjustH(this);
        });
      });
      /**
                       * 重置高度 
                       * @param {Object} elem
                       */
      function _adjustH(elem) {
        var $obj = jQuery(elem);
        return $obj
          .css({ height: $obj.attr("_initAdjustHeight"), "overflow-y": "hidden" })
          .height(elem.scrollHeight);
      }
    }
  });