1 xml文件格式

<?xml version="1.0" encoding="utf-8"?>
<userInfo>
  <userName>sa</userName>
  <userPwd>111111</userPwd>
</userInfo>

2 关键代码

2.1 MUserInfo.cs

// ***********************************************************************
// Assembly         : XML操作
// Author           : Amy
// Created          : 02-17-2014
//
// Last Modified By : Amy
// Last Modified On : 02-17-2014
// ***********************************************************************
// <copyright file="MUserInfo.cs" company="Microsoft">
//     Copyright (c) Microsoft. All rights reserved.
// </copyright>
// <summary></summary>
// ***********************************************************************

namespace XML操作
{
    /// <summary>
    /// Class MUserInfo.
    /// </summary>
    public class MUserInfo
    {
        /// <summary>
        /// The user name
        /// </summary>
        private string userName = string.Empty;

        /// <summary>
        /// The user password
        /// </summary>
        private string userPwd = string.Empty;

        /// <summary>
        /// Gets or sets the name of the user.
        /// </summary>
        /// <value>The name of the user.</value>
        public string UserName
        {
            get { return userName; }
            set { userName = value; }
        }

        /// <summary>
        /// Gets or sets the user password.
        /// </summary>
        /// <value>The user password.</value>
        public string UserPwd
        {
            get { return userPwd; }
            set { userPwd = value; }
        }

    }
}

2.2 XmlOperate.cs

// ***********************************************************************
// Assembly         : XML操作
// Author           : Amy
// Created          : 02-17-2014
//
// Last Modified By : Amy
// Last Modified On : 02-18-2014
// ***********************************************************************
// <copyright file="XMLOperate.cs" company="Microsoft">
//     Copyright (c) Microsoft. All rights reserved.
// </copyright>
// <summary></summary>
// ***********************************************************************

using System.Xml;

namespace XML操作
{
    /// <summary>
    /// Class XMLOperate.
    /// </summary>
    public class XMLOperate
    {
        /// <summary>
        /// Loads the XML.
        /// </summary>
        /// <param name="xmlfileName">Name of the xmlfile.</param>
        /// <returns>System.String.</returns>
        public static string LoadXML(string xmlfileName)
        {
            string result = string.Empty;
            XmlDocument xml = new XmlDocument();
            xml.Load(@xmlfileName);
            return xml.InnerXml.ToString();
        }

        /// <summary>
        /// Saves the XML.
        /// </summary>
        /// <param name="xmlContent">Content of the XML.</param>
        /// <param name="xmlFileName">Name of the XML file.</param>
        public static void SaveXML(string xmlContent, string xmlFileName)
        {
            XmlDocument xml = new XmlDocument();
            xml.LoadXml(xmlContent);
            xml.Save(@xmlFileName);
        }

        /// <summary>
        /// Gets the user information by executable ml.
        /// </summary>
        /// <param name="fileName">Name of the file.</param>
        /// <returns>MUserInfo.</returns>
        public static MUserInfo GetUserInfoByXMl(string fileName)
        {
            MUserInfo model = new MUserInfo();
            XmlDocument xml = new XmlDocument();
            xml.Load(@fileName);
            XmlNode xmlUserName = xml.SelectSingleNode("userInfo/userName");
            if (xmlUserName != null)
            {
                model.UserName = xmlUserName.InnerText.Trim();
            }

            XmlNode xmlUserPwd = xml.SelectSingleNode("userInfo/userPwd");
            if (xmlUserPwd != null)
            {
                model.UserPwd = xmlUserPwd.InnerText.Trim();
            }
            return model;
        }

        /// <summary>
        /// Sets the user information automatic XML.
        /// </summary>
        /// <param name="flieName">Name of the flie.</param>
        /// <param name="model">The model.</param>
        public static void SetUserInfoToXML(string flieName, MUserInfo model)
        {
            XmlDocument xml = new XmlDocument();
            xml.Load(@flieName);
            XmlNode xmlUserName = xml.SelectSingleNode("userInfo/userName");
            if (xmlUserName != null)
            {
                xmlUserName.InnerText = model.UserName;
            }

            XmlNode xmlUserPwd = xml.SelectSingleNode("userInfo/userPwd");
            if (xmlUserPwd != null)
            {
                xmlUserPwd.InnerText = model.UserPwd;
            }

            xml.Save(@flieName);
        }

    }
}

C# XML 操作