On the client side, use $. ajax :
$.ajax({
type: "POST",
url: "users/save",
data: "name=John&location=Boston",
success: function(msg){
alert( "Data Saved: " + msg );
}
From the ajax handle on the server side:
public ActionResult Save(string name, string location)
{
return new JsonResult(){Data = "User was saved!"};
}
Use JsonResult to return a json string to the client and JSON.parse to parse the client side json string.
ajax, $.ajax JsonResult, ajax, {data:"jsonString", messagess: [], redirect_url } ..
.