C#/XML用XML文件填充TreeView

im试图从xml文件填充树视图。

输出图像：https://i.stack.imgur.com/3HSCu.png

因此，正如您所看到的，父元素加载得很好，但子元素（元素）加载得不好。所有子节点都加载到所有父节点中。但是xml并不是这样的。

这是XML代码：

<?xml version="1.0" encoding="utf-8" ?> 
<toolbox>
<parent id="p1" caption="All Elements" class="parent">
  <element id="1" name="Button" />
  <element id="2" name="Label" />
  <element id="3" name="Inputfield" />
  <element id="4" name="Textarea" />
  <element id="5" name="Image" />
  <element id="6" name="Background" />
  <element id="7" name="TreeView" />
</parent>
<parent id="p2" caption="Some Elements 1" class="parent">
  <element id="1" name="Button" />
  <element id="2" name="Label" />
  <element id="3" name="Inputfield" />
</parent>
<parent id="p3" caption="Some Elements 2" class="parent">
  <element id="4" name="Textarea" />
  <element id="5" name="Image" />
  <element id="6" name="Background" />
  <element id="7" name="TreeView" />
</parent>
</toolbox>

这是C#代码：

    public void loadElements(string XML_Elements, TreeView Elements_Tree){
        XmlDocument XMLDocument =  new XmlDocument();
        XMLDocument.Load(XML_Elements);
        Elements_Tree.Nodes.Clear();
        Elements_Tree.BeginUpdate();
        XmlNodeList XMLParent = XMLDocument.SelectNodes("toolbox/parent"); 
        foreach(XmlNode xmlparent in XMLParent){
            //add parents
            string Parent_Caption = xmlparent.Attributes["caption"].Value;
            TreeNode parents = Elements_Tree.Nodes.Add(Parent_Caption);
            //add childs
            XmlNodeList XMLChilds = XMLDocument.SelectNodes("toolbox/parent/element");
            foreach (XmlNode xmlchild in XMLChilds)
            {
                string Child_Name = xmlchild.Attributes["name"].Value;
                parents.Nodes.Add(Child_Name);
            }
        }            
    }

XmlNodeList XMLChilds = XMLDocument.SelectNodes("toolbox/parent[@caption='" + Parent_Caption  + "']/element");

XmlNodeList XMLChilds = xmlparent.SelectNodes("element");