问题
RedirectToAction
is protected, and we can use it only inside actions. But if I want to redirect in a filter?
public class IsGuestAttribute: ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
if (!Ctx.User.IsGuest)
filterContext.Result = (filterContext.Controller as Controller)
.RedirectToAction("Index", "Home");
}
}
回答1:
RedirectToAction
is just a helper method to construct a RedirectToRouteResult()
, so what you do is simply create a new RedirectToRouteResult()
passing along a RouteValueDictionary()
with values for your action.
Complete sample based on code from @Domenic in the comment below:
public class IsGuestAttribute: ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
if (!Ctx.User.IsGuest)
{
filterContext.Result = new RedirectToRouteResult(
new RouteValueDictionary
{
{ "controller", "Home" },
{ "action", "Index" }
});
}
}
}
回答2:
Here's a code example:
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
if (!Ctx.User.IsGuest)
{
RouteValueDictionary redirectTargetDictionary = new RouteValueDictionary();
redirectTargetDictionary.Add("action", "Index");
redirectTargetDictionary.Add("controller", "Home");
filterContext.Result = new RedirectToRouteResult(redirectTargetDictionary);
}
}
回答3:
I know that I'm a little bit late to the party, but I used veggerby's solution and built a helper class that may be useful to some people, so I wanted to provide it here:
public static class ActionFilterHelpers
{
public static void Redirect(this ActionExecutingContext filterContext, String controller, String action, object routeValues)
{
filterContext.Result = Redirect(controller, action, routeValues);
}
public static ActionResult Redirect(String controller, String action, object routeValues)
{
var routeValues = new RouteValueDictionary();
routeValues["controller"] = controller;
routeValues["action"] = action;
foreach (var keyValue in new ObjectDictionary(routeValues))
routeValues.Add(keyValue.Key, keyValue.Value);
return new RedirectToRouteResult(routeValues);
}
}
I provided both a static method that returns a redirect ActionResult
and an extension method that extends filterContext
. Hope someone finds this useful.
ObjectDictionary
is a class that uses reflection to create a dictionary from the properties of the object from which it is constructed. I didn't include that code because I believe there is a better way to do that somewhere in the framework. I haven't found it yet, but I don't want others to inherit my potential bugs.
回答4:
Security/Authorization/Authentication Filters should use the AuthorizeAttribute and IAuthorizationFilter.
public class IsGuestAttribute: AuthorizeAttribute, IAuthorizationFilter
{
public void OnResultExecuted(ResultExecutedContext filterContext)
{
}
public void OnActionExecuting(ActionExecutingContext filterContext)
{
if (!Ctx.User.IsGuest)
{
filterContext.Result = new RedirectToRouteResult(
new RouteValueDictionary
{
{ "controller", "Home" },
{ "action", "Index" }
});
}
}
}
回答5:
Usage: filterContext.RedirectToAction("Login", "Account");
Here's a helper class I wrote with some extension methods written to provide RedirectToAction functionality in more places. This is far too late for the OP but hopefully it helps someone!
public static class RedirectHelper
{
// RedirectToAction Extension Methods
public static void RedirectToAction(this HttpResponseBase response, String action, String controller, object routeValues = null, bool endResponse = false)
{
response.RedirectToRoute(CreateRoute(action, controller, routeValues));
if (endResponse) response.End();
}
public static void RedirectToAction(this HttpResponse response, String action, String controller, object routeValues = null, bool endResponse = false)
{
response.RedirectToRoute(CreateRoute(action, controller, routeValues));
if (endResponse) response.End();
}
public static void RedirectToAction(this ActionExecutingContext filterContext, String action, String controller, object routeValues = null, bool endResponse = false)
{
if (endResponse) filterContext.HttpContext.Response.RedirectToAction(action, controller, routeValues, true);
else filterContext.Result = new RedirectToRouteResult(CreateRoute(action, controller, routeValues));
}
public static void RedirectToAction(this ExceptionContext filterContext, String action, String controller, object routeValues = null, bool endResponse = false)
{
if (endResponse) filterContext.HttpContext.Response.RedirectToAction(action, controller, routeValues, true);
else {
filterContext.ExceptionHandled = true;
filterContext.Result = new RedirectToRouteResult(CreateRoute(action, controller, routeValues));
}
}
// Route Value Derivation
public static RouteValueDictionary CreateRoute(String action, String controller, object routeValues = null)
{
RouteValueDictionary result = routeValues != null ?
HtmlHelper.AnonymousObjectToHtmlAttributes(routeValues) :
new RouteValueDictionary();
result["controller"] = controller;
result["action"] = action;
return result;
}
}
There are more ControllerContexts that are not included but it should be fairly easy to add your own based on your needs.
来源:https://stackoverflow.com/questions/550995/how-to-get-filter-to-redirect-to-another-action