How to use ajax in asp.net MVC - asp.net-mvc-3

Question

How can I return a class object from Ajax in asp.net MVC....???
Example:
Ajax call from html:
$.ajax({
type: 'POST',
url: '/Tutorial/Web/AlignmentRule/GetAlignmentDetails',
data: { alignmentRuleId: alignmentRuleId },
success:
function (data) {
alert(data.Id);
alert(data.alignmentData.Id);
$("#ruleName").val(data.alignmentData.Name);
$("#level").val(data.alignmentData.Id);
},
error:
function () {
alert("Server Error!!!!");
},
dataType: 'JSON',
async: false
});
and Action method in contorller is:
public virtual JsonResult GetAlignmentDetails(int alignmentRuleId)
{
var alignmentData = _allignmentRuleRepository.GetAlignmentById(alignmentRuleId);
return Json( alignmentData );
}
And I want to return a list of alignmentRule class objects also....

Answer 1

you can compose your return object as you want, for example, create a ViewModel as decorator to hold everything you want to pass, like:
var json = new JsonViewModel() {
alignmentData = alignmentData,
rules = yourRules
};
return Json(json);

Answer 2

The error is thrown because by default MVC framework does't allow you to respond to an HTTP GET request with a JSON (because of security reasons).
In order to make it work, when you retrurn Json in your action, you need to specify JsonRequestBehavior.AllowGet
[HttpPost]
public virtual JsonResult GetAlignmentDetails(int alignmentRuleId)
{
var alignmentData = _allignmentRuleRepository.GetAlignmentById(alignmentRuleId);
return Json( alignmentData, JsonRequestBehavior.AllowGet);
}
EDIT
Annotate your action with [HttpPost] attribute.
For further investigation on this topic check this article