如何通过将树视图中的节点绑定到 XML 文档的节点来显示树节点

Question

我有一个树视图，在选择节点时，属性和值必须显示在列表框中。
在treeView1_AfterSelect中，文本解析代码取决于树视图中节点的文本表示，该文本表示可以随时更改并破坏列表显示的整个逻辑。 应该通过将树视图中的节点绑定到 XML 文档的节点来消除树视图和列表显示之间的这种强依赖性，以便可以使用原始 Xml 数据来显示列表中的文本。这里应该写什么？

private static void AddingNodesToTree(XmlNode xmlNode,TreeNode tnode)  
        {  
            //Adding nodes to tree while looping through the entire XML file  
            if (xmlNode.HasChildNodes)  
            {  
                XmlNodeList nodeList = xmlNode.ChildNodes;                 
                for (int i = 0; i <= nodeList.Count - 1; i++)  
                {  
                    XmlNode xmladdtreeNode = xmlNode.ChildNodes[i];  
                    String nodetype = "" + xmladdtreeNode.NodeType;  
                    if (nodetype.Equals("Text") || nodetype.Equals("Comment"))    
                    {  
                    tnode.Nodes.Add(new TreeNode(xmladdtreeNode.InnerText));           
                    }  
                    else                                                    
                    {  
                        String name = "<" + xmladdtreeNode.Name;  
                        XmlAttributeCollection attCol = xmladdtreeNode.Attributes; 
                        foreach (XmlAttribute xmlatt in attCol)  
                        {  
                        name += " " + xmlatt.Name + "=\"" + xmlatt.Value + "\"";  
                        }  
                        name +=  ">";  
                        TreeNode tn = new TreeNode(xmladdtreeNode.Name);  
                        tn.Text = name;  
                        tnode.Nodes.Add(tn);  
                        TreeNode treeNode = tnode.Nodes[i];  
                        AddingNodesToTree(xmladdtreeNode,treeNode);   
                        }  
                }//for  
            }//if  
          else 
            {  
                tnode.Text = xmlNode.OuterXml.Trim();
            }//else   
        }//AddingNodesToTree  
        //To show Attributes and values of selected Nodes.  
        private void treeView1_AfterSelect(object sender,TreeViewEventArgs e)  
        {  
            TreeNode treenode = e.Node;   //Node selected in Treeview            
            String text = treenode.Text;  
            String relevent = text;  
            Boolean flag = true;  
            while (flag)  
            {  
                int SpaceIndex = relevent.IndexOf(" ");  
                if (SpaceIndex != -1)  
                {  
                    int indexofEqual = relevent.IndexOf('=', SpaceIndex);  
                    if (indexofEqual != -1)  
                    {  
                        int indexOFValue = relevent.IndexOf("\"", indexofEqual + 2);  
                        if (indexOFValue != -1)  
                        {  
  String attribute = relevent.Substring(SpaceIndex + 1, indexofEqual - SpaceIndex - 1);   
  String value = relevent.Substring(indexofEqual + 2, indexOFValue - indexofEqual - 2);   
  listBox1.Items.Add("Attribute : " + attribute + "   Value : " + value);                 
                            relevent = relevent.Substring(indexOFValue);
                        }
                        else
                        {
                         listBox1.Items.Add("Bad format of the xml file for this node");
                         flag = false;
                        }
                    }
                    else
                    {
                        flag = false;
                    }
                }
                else
                {
                    flag = false;
                }
            }
        }//AfterSelect()

谢谢....

Answer 1

如果我正确理解了这个问题，那么当选择 TreeNode 时，您希望返回到 XmlNode。 通常的解决方案是将 XmlNode 存储在 Tag 属性中：

TreeNode tn = new TreeNode();  
tn.Text = name;  
tn.Tag = xmladdtreeNode;

以及 AfterSelect 中

TreeNode treenode = e.Node; 
XmlNode xmlNode = (XmlNode) treeNode.Tag;

Answer 2

我尝试了这个，但在这一行得到了 NullRefrenceException
foreach (XmlAttribute xmlatt in attCol) on attcol

这是我编写的代码..

private void treeView1_AfterSelect(object sender, System.Windows.Forms.TreeViewEventArgs e)
    {
        listBox1.Items.Clear();
        XmlNode xNode = e.Node.Tag as XmlNode;
        XmlAttributeCollection attCol = xNode.Attributes; 
        foreach (XmlAttribute xmlatt in attCol)
        {
            listBox1.Items.Add(xmlatt.Name);
            listBox1.Items.Add(xmlatt.Value);

        }
    } //AfterSelect()