XmlTextReader xml-. :
string textToParse = "<e a=\"x\ty\rz\n\" />" ;
using (var sr = new StringReader(textToParse)) {
using (var xr = new XmlTextReader(sr)) {
var xd = XDocument.Load(xr);
System.Console.WriteLine(xd.ToString());
}
}
<e a="x	y
z
" />