XmlTextWriter的一个小问题，可是我不熟悉C#, 刚开始学

Question

下面这段代码为什么返回的是空串啊？请各位看看是哪里错了
MemoryStream msXml = new MemoryStream();
XmlTextWriter xmlWriter = new XmlTextWriter(msXml,Encoding);
xmlWriter.WriteStartElement("Growth10K");
xmlWriter.WriteString("ok");
XmlTextReader xmlReader = new XmlTextReader(msXml);
return xmlReader.ReadOuterXml();

Answer 1

不好意思，代码弄错了点，下面的才是
MemoryStream msXml = new MemoryStream();
XmlTextWriter xmlWriter = new XmlTextWriter(msXml,Encoding);
xmlWriter.WriteStartElement("Growth10K");
xmlWriter.WriteString("ok");'
xmlWriter.WriteEndElement();
XmlTextReader xmlReader = new XmlTextReader(msXml);
return xmlReader.ReadOuterXml();

Answer 2

XmlTextWriter xmlWriter = new XmlTextWriter(@"c:\x.xml", Encoding.UTF8);
xmlWriter.WriteStartElement("Growth10K");
xmlWriter.WriteString("ok");
xmlWriter.WriteEndElement();
xmlWriter.Flush();
xmlWriter.Close();
XmlReader xmlReader = XmlReader.Create(@"c:\x.xml");
if (xmlReader.Read())
{
  return (xmlReader.ReadOuterXml());
}
else
{ return null;}
xmlReader.Close();

Answer 3

MemoryStream msXml = new MemoryStream();
    XmlTextWriter xmlWriter = new XmlTextWriter(msXml, Encoding.UTF8);
    xmlWriter.WriteStartElement("Growth10K");
    xmlWriter.WriteString("ok");
    xmlWriter.WriteEndElement();
    xmlWriter.Flush();
    Response.Write(msXml.Length.ToString());
    msXml.Position = 0;
    XmlReader xmlReader = XmlReader.Create(msXml);if (xmlReader.Read())
{
  return (xmlReader.ReadOuterXml());
}
else
{ return null;}
    msXml.Close();
    xmlWriter.Close();
    xmlReader.Close();

Answer 4

这样既可
MemoryStream msXml = new MemoryStream();
XmlTextWriter xmlWriter = new XmlTextWriter(msXml, Encoding.UTF8);
xmlWriter.WriteStartElement("Growth10K");
xmlWriter.WriteString("ok");
xmlWriter.WriteEndElement();
xmlWriter.Flush();
msXml.Position = 0;
XmlReader xmlReader = XmlReader.Create(msXml);if (xmlReader.Read())
{
  return (xmlReader.ReadOuterXml());
}
else
{
  return null;
}
msXml.Close();
xmlWriter.Close();
xmlReader.Close();

Answer 5

xmlWriter.Flush(); //必须
msXml.Position = 0; //必须XmlReader xmlReader = XmlReader.Create(msXml);if (xmlReader.Read()) //必须