xml from client to server

how to format xml data at client for sending to server

[sunswept]

what should be used to format data at a client to xml in order to send it via an ajax request?

I found some code snippets that do it but i want to know what is the standard method to do it. Does everyone use some standard js libs? if yes then which one is recommended?

I read some arguments (efficency) about not using xml for sending from client to server, if the amount of data to send to server is large and divided in sections should i use xml or try plain text key-value pairs?
Thanks in advance

[whoisgregg]

I've always used key value pairs for my ajax requests. I typically also return the data from the server using JSON instead of XML. So, use of AJAX can be completely XML free.