AFIK, There is no direct way of checking enlishment.Long gape i was refering below code block to check.
public static bool CheckEnlisted(SqlConnection con)
{
object myObject = typeof(SqlConnection).GetField("_innerConnection", BindingFlags.Instance | BindingFlags.NonPublic).GetValue(con);
myObject = myObject.GetType().GetField("_enlistedTransaction", BindingFlags.Instance | BindingFlags.NonPublic);
return myObject != null;
}
Hope this would help you.
Lingaraj Mishra