GeckoFx (4)使用 treeview 展示 dom 数树

GeckoFx (4)使用 treeview 展示 dom 数树
使用 DocumentCompleted 事件，在页面加载完成后构建一个 dom 树使用 treeview 控件。
treeHtml： treeview 控件；
browser：Gecko.GeckoWebBrowser 控件；


注册事件：

browser.DocumentCompleted += browser_DocumentCompleted;

/// <summary>
/// 文档加载完成事件
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void browser_DocumentCompleted(object sender, Gecko.Events.GeckoDocumentCompletedEventArgs e)
{
  ShowHtmlTree();
}

/// <summary>
/// 构建dom树
/// </summary>
private void ShowHtmlTree()
{
  this.treeHtml.Nodes.Clear();
  var domRoot = browser.DomDocument;
  StringBuilder attrStr = new StringBuilder();
  Func<GeckoNode, string> getTag = (node) =>
  {
    attrStr.Clear();
    if (node.NodeName.Equals("STYLE") ||
      node.NodeName.Equals("SCRIPT"))
    {
      return string.Format("<{0}>...</{0}>",node.NodeName.ToLower());
    }
    //var element = node as GeckoHtmlElement;
    string innerText = string.Empty;
    GeckoElement element = node.GetEventTarget().CastToGeckoElement();
    //
    if (element != null && 
      element.ChildNodes.Count()==1 &&
      element.ChildNodes[0].NodeType == NodeType.Text)
    {
      innerText = element.TextContent;
    }
    attrStr.AppendFormat("<{0}", node.NodeName.ToLower());
    //构建属性
    if (node.HasAttributes && element != null)
    {
      foreach (var attr in element.Attributes)
      {
        attrStr.Append(
          string.Format(" {0}=\"{1}\"", attr.NodeName, attr.NodeValue));
      }
    }
    //内容
    attrStr.AppendFormat(">{0}</{1}>", innerText, node.NodeName.ToLower());
    return attrStr.ToString();
  };
  //递归构建树
  Func<GeckoNode, TreeNode> buildTree = null;
  buildTree = (rNode) =>
  {
    if (rNode == null)
      return null;
    TreeNode tnode = new TreeNode()
    {
      Text = getTag(rNode),
      Tag = rNode
    };
    if (rNode.ChildNodes == null || !rNode.ChildNodes.Any())
      return null;
    foreach (var cNode in rNode.ChildNodes)
    {
      var ctnode = buildTree(cNode);
      if (ctnode != null)
        tnode.Nodes.Add(ctnode);
    }
    return tnode;
  };
  var treeRoot = buildTree(domRoot);
  if (treeRoot!=null)
    this.treeHtml.Nodes.Add(treeRoot);
  this.treeHtml.ExpandAll();
}