C#创建XML字符串

//webService

using System;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Xml;
using System.Text;
using System.IO;

[WebService(Namespace = "webservice")] //(Namespace = "http://localhost/webserver/")
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
public class Service : System.Web.Services.WebService
{
    public Service () {

        //如果使用设计的组件，请取消注释以下行 
        //InitializeComponent(); 
    }

    [WebMethod]
    public string HelloWorld() {
        return "Hello World";
    }

    [WebMethod] 
    public  string  show(string  yourname) 
    { 
        //return  "http://aaaaa"+"欢迎"+yourname;

       //生成xml字符串：
        using (StringWriter sw = new StringWriter())
        {
            XmlTextWriter xtw = new XmlTextWriter(sw);
            xtw.Formatting = Formatting.Indented;
            xtw.WriteStartDocument();

            xtw.WriteStartElement("root");

            //test
            xtw.WriteStartElement("test");
            xtw.WriteString("test content");
            xtw.WriteEndElement();

            //test2
            xtw.WriteStartElement("test2");

            //testSub
            xtw.WriteStartElement("testSub");
            xtw.WriteString("Sub content");
            xtw.WriteEndElement();

            xtw.WriteEndElement();
        

            xtw.WriteEndElement();//root
            xtw.WriteEndDocument();            
          
            string result = sw.ToString();

            return result.Replace("utf-8", "gb2312").Replace("utf-16", "gb2312");
        } 
    }

    
    [WebMethod] 
    public string parseXML()
    {
        /**/////解析xml：
        string strInput = "<?xml version='1.0' encoding='utf-16'?><foo><bar /></foo>";
        XmlTextReader r = new XmlTextReader(new StringReader(strInput));
        MemoryStream ms = new MemoryStream();
        XmlTextWriter w = new XmlTextWriter(ms, Encoding.UTF8);
        w.WriteNode(r, false);
        w.Flush();
        ms.Position = 0;
        StreamReader sr = new StreamReader(ms);
        string strOutput = sr.ReadToEnd();
        return strOutput.Replace("utf-8", "gb2312").Replace("utf-16", "gb2312");
        //Console.WriteLine("Input = {0}, Output = {1}", strInput.Length, strOutput.Length);
    } 
    
}