Get Action parameters from mvc - asp.net

Question

I'm trying to get the parameters of a request on exception and log them. How can I get action parameters from a request if the parameter is an object in asp.net mvc? I can only get the parameters if I send in the parameters like this:
public virtual ActionResult TestAction(string A,string B){
}
But not like this:
public virtual ActionResult TestAction(ObjectQuery query){
}
My code:
protected override void OnException(ExceptionContext filterContext)
{
string action = filterContext.RouteData.Values["action"].ToString();
string controller = filterContext.RouteData.Values["controller"].ToString();
string parameters = filterContext.HttpContext.Request.QueryString
}
EDIT:
QueryString returns empty:

Answer 1

You should use reflection to achieve this:
var parameters = MethodBase.GetCurrentMethod().GetParameters();
foreach (ParameterInfo param in parameters)
{
//do your logging here
}

Answer 2

I maybe over simplifying it, but you can get the parameters passed to the action using the Request.Form or Request.QueryString. The nice thing about them is they are of the type NameValueCollection which makes it easy to merge them together.
Then the exception is being thrown on the respective controller so you can get the method signature via reflection, albeit without the named parameter.
Using the simple code below properly gave the parameters passed to the action and doesn't care if it is a POST or GET operation.
protected override void OnException(ExceptionContext filterContext)
{
//Get all the info we need to define where the error occured and with what data
var param = new NameValueCollection {Request.Form, Request.QueryString};
var controller = filterContext.RouteData.Values["controller"].ToString();
var action = filterContext.RouteData.Values["action"].ToString();
var signature = filterContext.Controller.GetType().GetMethod(action).ToString();
//Let's write it to the stream in this case
Response.Write(string.Format("<h3>Controller: {0}</h3>", controller));
Response.Write(string.Format("<h3>Action: {0}</h3>", action));
Response.Write(string.Format("<h4>Signature: {0}</h4>", signature));
foreach (var key in param.AllKeys)
{
Response.Write(string.Format("<strong>Key:</strong> {0} = {1}<br />", key, param[key]));
}
Response.End();
}
There are some downsides I would imagine though. Collections will probably be represented in a very unfriendly way. Data which wasn't supposed to bind with the specific model will be shown as well.