我需要创建一个像这样的xml文件,并可以立即将其发布到url上
<Student>
<Name>John</Name>
<Age>17</Age>
<Marks>
<Subject>
<Title>Maths</Title>
<Score>55</Score>
</Subject>
<Subject>
<Title>Science</Title>
<Score>50</Score>
</Subject>
</Marks>
</Student>
string marksxml = "<Marks><Subject><Title>Maths</Title><Score>55</Score></Subject><Subject><Title>Science</Title><Score>50</Score></Subject></Marks>";
XDocument doc = new XDocument(new XElement("Student",
new XElement("Name", "John"),
new XElement("Age", "17")));
如何将字符串marksxml嵌入到XDocument中?