使用C＃App设置3DCart API

I have been trying to create an application to go through our database at a set interval and update/add any new items to 3DCarts database. Their code example uses soap in an xml file to send 1 request per call. So I need to to be able to generate the xml I need with the items information on the fly before sending it. I have done hardly anything with XML files like this and cannot figure out how to create the chunk of code I need and send it. One method that has been suggested is create a file but still executing has been a problem and would be very inefficient for a large number of items. Here is what I have so farI have been trying to create an application to