How to create xml with this style via C# code? -

i want create via c# code xml this:

<title>           <a>             <aa=aa,cc=cc,dd=dd/>       </a>       <b>             <bbbbbbbbbbbbb.udl/>          </b> </title> 

with code should create tree thist? how put symbols "=" , "." inside name?

only using stringbuilder, since sample gave not valid xml.

did mean use syntax like:

<aa foo="bb" bar="cc"/>