Transfer node from a treeView to another treeview in c#

Is very important , am working for an projet and want to trasnfert node from a treeview to another ( XML node ) . First , I browse my XML file in a treeview then I do the same with the xml file destination. ( Winforms). I select a node then I want to move it to the other tree. my XML file is like this one :

     <obje> 
<category  title="B">
        <category_value title="C0">
            <object id="1000" name="DM_AAAA">
                <child id="3795" x="0" y="0"/>
                <child id="3798" x="0" y="238"/>
                <child id="13794" x="0" y="44"/>

            </object>
            <object background_colour="230" id="1004" name="DM_PPPP">
                <child id="3795" x="0" y="0"/>
                <child id="3798" x="0" y="238"/>
                <child id="13794" x="0" y="44"/>
                <child id="13794" x="239" y="44"/>

            </object>

        </category_value>
    </category>
    <category  title="Ma">
        <category_value title="C0">
            </object  id="1211" name="DM_Reg" >


            <object  id="5063"  name="SK" >
                <child id="14998" x="0" y="0"/>
                <child id="20955" x="0" y="0"/>
            </object>

        </category_value>
    </category>
</obje>

then , My code is :

   private void TransfertVersFichier2_Click(object sender, EventArgs e)
        {
            AllCheckedNodes.Clear();
            if (GetAllCheckedNodes(treeView1.Nodes).Count == 0)
            {
                MessageBox.Show("Veuillez séléctionner un node à déplacer");
            }
            else if (GetAllCheckedNodes(treeView1.Nodes).Count == 1)
            {
                TreeNode nodeToTransfer = GetAllCheckedNodes(treeView1.Nodes)[0];
                string nodeToTransferTagName = nodeToTransfer.Name;
                string checkedId = nodeToTransfer.Tag.ToString();


                    var r_nodes = doc.GetElementsByTagName(nodeToTransferTagName);
                    XmlNode xmlNodeToTransfer = null;
                    foreach (XmlNode r_node in r_nodes)
                    {

                        if (r_node.Attributes != null && r_node.Attributes["id"] != null && r_node.Attributes["id"].Value == checkedId)
                        {
                            xmlNodeToTransfer = r_node;
                        }
                        else if (r_node.Attributes != null && r_node.Attributes["title"] != null && r_node.Attributes["title"].Value == checkedId)
                        {
                            xmlNodeToTransfer = r_node;
                        }
                        else if (r_node.Attributes != null && r_node.Attributes["name"] != null && r_node.Attributes["name"].Value == checkedId)
                        {
                            xmlNodeToTransfer = r_node;
                        }
                    }

                    if (xmlNodeToTransfer != null)
                    {
                        if (xmlNodeToTransfer.ParentNode.Attributes != null && xmlNodeToTransfer.ParentNode.Attributes["id"] != null)
                        {
                            /*TreeNode[] treeNodes_ch = treeView2.Nodes.Find(xmlNodeToTransfer.ParentNode.Name, true);
                            foreach (TreeNode ch_node in treeNodes_ch)
                            {
                                if (ch_node.Tag.ToString() == xmlNodeToTransfer.ParentNode.Attributes["id"].Value)
                                {
                                    ch_node.Nodes.Insert(0, nodeToTransfer);
                                }
                            }*/

                            var tr_nodes = doc2.GetElementsByTagName(nodeToTransfer.Parent.Name);
                            foreach (XmlNode nodeToTransferParent in tr_nodes)
                            {
                                if (nodeToTransferParent.Attributes != null && nodeToTransferParent.Attributes["id"] != null && nodeToTransferParent.Attributes["id"].Value == xmlNodeToTransfer.ParentNode.Attributes["id"].Value)
                                {
                                    XmlNode xml_nd = xmlNodeToTransfer.Clone();
                                    nodeToTransferParent.AppendChild(xml_nd);
                                }
                            }
                            doc2.Save(Path2);
                        }
                        else if (xmlNodeToTransfer.ParentNode.Attributes != null && xmlNodeToTransfer.ParentNode.Attributes["title"] != null)
                        {
                            MessageBox.Show(xmlNodeToTransfer.ParentNode.Attributes["title"].Value);
                        }
                        else if (xmlNodeToTransfer.ParentNode.Attributes != null && xmlNodeToTransfer.ParentNode.Attributes["name"] != null)
                        {
                            MessageBox.Show(xmlNodeToTransfer.ParentNode.Attributes["name"].Value);
                        }
                    }

            }
            else
            {
                MessageBox.Show("Veuillez séléctionner un seul node àdéplacer");
            }
        }