private void populateTreeControl(System.Xml.XmlNode document,System.Windows.Forms.TreeNodeCollection nodes)
  {
   foreach (System.Xml.XmlNode node in document.ChildNodes)
   {
    string text = (node.Value != null ? node.Value : (node.Attributes != null && node.Attributes.Count > 0) ?node.Attributes[1].Value : node.Name); //A1
    TreeNode new_child = new TreeNode(text);
    nodes.Add(new_child);
    populateTreeControl(node, new_child.Nodes); //A2
   }
  }
大体是个什么意义??尤其是A1和A2

就是
string text = (node.Value != null ? node.Value : (node.Attributes != null && node.Attributes.Count > 0) ?node.Attributes[1].Value : node.Name);
这句话看得不是很明白.