ajax - POST values from inline edit -

i used code change table cell span input on click- replace 1 inline edit want post values through ajax , not sure how. want post comments users have edited , update them on database how got far:

$.ajax({         type: "post",         url: "comments.php",//to update comments         data: "data"                  }); 

not sure put next. possible post values when user click out of input area? , data have serialize?
in advance!

$.ajax({         type: "post",         url: "comments.php",//to update comments         data: {"comments":$("yourformid").serialize()},         success:function(res)          {            //do ever want           }             }); 

and in comments.php print_r($_post) give posted array via ajax

if use form.serialize data form submitted