How to add input check in a Linq Query to build XML only if input is valid

I have an input value that I need to use to build out an XML. Only if the value exists, do I need to build the sub-elements.

Example

string classInput="something";     
XDocument classes = new XDocument(
                     new XElement("Classes",
                                         new XElement("Class",
                                                 new XElement("Name", classInput))
                                                ));

returns what I want:

<Classes>
  <Class>
    <Name>something</Name>
  </Class>
</Classes>

However, the query above returns:

<Classes>
  <Class>
    <Name></Name>
  </Class>
</Classes>

in the case classInput is null or empty, but I want it build the sub-XML only if classInput is a non-empty string. i.e In the above case, I would just like to build out:

<Classes /> if, say classInput = "";

Tried to add a check in the query, but then it processes the string classInput character wise, instead of as a string. Then I get

 <Classes>
      <Class>
        <Name>something</Name>
      </Class>
    </Classes>

I have some more inputs that I have to build some more sub-elements in the same way, so I need a solution t开发者_运维问答hat can be extensible.

Check the input with a conditional operator and return null if the input is null or empty:

XDocument classes = new XDocument(
                      new XElement("Classes", String.IsNullOrEmpty(classInput) ?
                          null :
                          new XElement("Class",
                              new XElement("Name", classInput))
                    ));