code: function getContent(node) {
      var text = '', atom;
      for (var i = 0; i<node.childNodes.length; i++) {
        if (node.childNodes[i].nodeType === 1) {
          atom = node.childNodes[i]._bfs_text;
        } else if (node.childNodes[i].nodeType === 3) {
          atom = node.childNodes[i].data;
        } else
          continue;
        if (text.match(/[\t ]+$/) && atom.match(/^[\t ]+/)) {
          text = text.replace(/[\t ]+$/,'') + ' ' + atom.replace(/^[\t ]+/, '');
        } else {
          text = text + atom;
        }
      }
      return text;
    }
docs: Get a node's content.