用c# xml做登录界面的问题

<users>
<user>
<name>lin</name>
<password>1</password>
</user>
<user>
<name>1</name>
<password>1</password>
</user>
</users>
这是我的xml，我想问下在登录时，怎么遍历这些进行判断用户是否操作

这个博客有篇文章，对你应该有帮助

http://lihanying1991.blog.163.com/

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Xml;

namespace WindowsApplication3
{
/// <summary>
/// Form1 的摘要说明。
/// </summary>
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Button button1;
private XmlDocument doc = new XmlDocument();
private XmlNode attrColl;
private System.Windows.Forms.Button button2;
private System.Windows.Forms.HelpProvider helpProvider1;
/// <summary>
/// 必需的设计器变量。
/// </summary>
private System.ComponentModel.Container components = null;