请各位高手指导指导。。。小弟先谢了。。。

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Web;
using System.Web.Services;
using System.Xml;
using System.Xml.Schema;
using System.IO;

namespace TalentPoolService
{
///
/// Service1 的摘要说明。
///
public class TalentPoolService : System.Web.Services.WebService
{
public string profile;

private const String m_XmlFile = "profiles.xml";
private XmlDocument xmlDocument;
private XmlNode selectNode;

public TalentPoolService()
{
//CODEGEN: 该调用是 ASP.NET Web 服务设计器所必需的
InitializeComponent();
}

#region 组件设计器生成的代码

//Web 服务设计器所必需的
private IContainer components = null;

///
/// 设计器支持所需的方法 - 不要使用代码编辑器修改
/// 此方法的内容。
///
private void InitializeComponent()
{
}

///
/// 清理所有正在使用的资源。
///
protected override void Dispose( bool disposing )
{
if(disposing && components != null)
{
components.Dispose();
}
base.Dispose(disposing);
}

#endregion

// WEB 服务示例
// HelloWorld() 示例服务返回字符串 Hello World
// 若要生成，请取消注释下列行，然后保存并生成项目
// 若要测试此 Web 服务，请按 F5 键

[WebMethod]
public string AddProfile(string nameIn, string addressIn, string postcodeIn, string sizeIn, string competenceIn)
{
string success = @"Adding success!";
xmlDocument = new XmlDocument();

XmlTextReader textReader = new XmlTextReader(m_XmlFile);
XmlValidatingReader reader = new XmlValidatingReader(textReader);
reader.ValidationType = ValidationType.DTD;

xmlDocument.Load(reader);
//return success;

textReader.Close();
//return success;

XmlElement newProfile = xmlDocument.CreateElement("Profile");

XmlElement nameEle = xmlDocument.CreateElement("Name");
nameEle.InnerText = nameIn;
newProfile.AppendChild(nameEle);

XmlElement addressEle = xmlDocument.CreateElement("Address");
addressEle.InnerText = addressIn;
newProfile.AppendChild(addressEle);

XmlElement postcodeEle = xmlDocument.CreateElement("Postcode");
postcodeEle.InnerText = postcodeIn;
newProfile.AppendChild(postcodeEle);

XmlElement sizeEle = xmlDocument.CreateElement("Size");
sizeEle.InnerText = sizeIn;
newProfile.AppendChild(sizeEle);

XmlElement compeEle = xmlDocument.CreateElement("Competence");
compeEle.InnerText = competenceIn;
newProfile.AppendChild(compeEle);

xmlDocument.DocumentElement.AppendChild(newProfile);

XmlTextWriter textWriter = new XmlTextWriter(m_XmlFile, System.Text.Encoding.UTF8);
textWriter.Formatting = Formatting.Indented;
xmlDocument.WriteContentTo(textWriter);
textWriter.Close();

return success;
}