performence issue of an XML reader

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Text;

using System.Windows.Forms;

using System.Xml;

namespace XMLReader

{

publicpartialclassXMLReader_WindowsBased :Form

public XMLReader_WindowsBased()

{

InitializeComponent();

}

privatevoid btnSelect_Click(object sender,EventArgs e)

{

ofdXMLFile.ShowDialog();

txtXmlFile.Text = ofdXMLFile.FileName;

}

privatevoid cmdLoad_Click(object sender,EventArgs e)

{

// Clear the tree.

// Load the XML Document

XmlDocument doc =newXmlDocument();

try

catch (Exception)

{

MessageBox.Show(" Error: The selected or entered XML file was not found! ");

return;

}

// Populate the TreeView.

// Expand all nodes.

privatevoid ConvertXmlNodeToTreeNode(XmlNode xmlNode,TreeNodeCollection treeNodes)

{

// Add a TreeNode node that represents this XmlNode.

TreeNode newTreeNode = treeNodes.Add(xmlNode.Name);

// Customize the TreeNode text based on the XmlNode

// type and content.

switch (xmlNode.NodeType)

{

caseXmlNodeType.ProcessingInstruction:

caseXmlNodeType.XmlDeclaration:

newTreeNode.Text ="<" + xmlNode.Name +" " + xmlNode.Value +">";

break;

caseXmlNodeType.Element:

newTreeNode.Text ="<" + xmlNode.Name +">";

break;

caseXmlNodeType.Attribute:

newTreeNode.Text ="ATTRIBUTE: " + xmlNode.Name;

break;

caseXmlNodeType.Text:

caseXmlNodeType.CDATA:

newTreeNode.Text = xmlNode.Value;

break;

caseXmlNodeType.Comment:

newTreeNode.Text ="<!--" + xmlNode.Value +"-->";

break;

}

// Call this routine recursively for each attribute.

// (XmlAttribute is a subclass of XmlNode.)

if (xmlNode.Attributes !=null)

{

foreach (XmlAttribute attributein xmlNode.Attributes)

{

ConvertXmlNodeToTreeNode(attribute, newTreeNode.Nodes);

}

}

// Call this routine recursively for each child node.

// Typically, this child node represents a nested element,

// or element content.

foreach (XmlNode childNodein xmlNode.ChildNodes)

{

ConvertXmlNodeToTreeNode(childNode, newTreeNode.Nodes);

}

}

privatevoid label2_Click(object sender,EventArgs e)

{

}

}

}

Issues:

It's ok to open small XML files. But for large XML files, it's fairly slow and loses response.

How should I enhance the codes to run fast? Is there any better solution?

Thanks.