Does anyone know if there is a reason why _ViewStart.cshtml wouldn't get picked up with a Custom ViewEngine in MVC 3?
My Views now live at
~\UI\Views\
~\UI\Views\Shared\
with ViewStart being at ~\UI\Views_ViewStart.cshtml.
I've cleared out the existing RazorViewEngine and replaced it with mine in the global.asax and all the views resolve properly except none of the layout pages get applied unless I specify it individually in each view.
My engine path format code is:
this.ViewLocationFormats = new[]
{
"~/UI/Views/{1}/{0}.cshtml",
"~/UI/Views/Shared/{0}.cshtml"
};
this.PartialViewLocationFormats = new[]
{
"~/UI/Views/Shared/{0}.cshtml",
"~/UI/Views/Shared/Partial/{0}.cshtml",
"~/UI/Views/{1}/Partial/{0}.cshtml"
};
this.AreaMasterLocationFormats = new[]
{
"~/UI/Views/Admin/Shared/{0}.cshtml"
};
this.AreaPartialViewLocationFormats = new[]
{
"~/UI/Views/Admin/Shared/{0}.cshtml",
"~/UI/Views/Admin/Shared/Partial/{0}.cshtml"
};
this.AreaViewLocationFormats = new[] { "~/UI/Views/Admin/{1}/{0}.cshtml" };
this.MasterLocationFormats = new[]
{
"~/UI/Views/{1}/{0}.cshtml",
"~/UI/Views/Shared/{0}.cshtml"
};
Thanks in advance,
Scott
Stupidity won this time, unfortunately. I had based my custom ViewEngine off some code I referenced from an article. Within the article, they detailed the override for CreateView. It had one of the boolean parameters (runViewStartPages) set to false but since it wasn't a named argument, I missed over it.
public class XyzViewEngine : RazorViewEngine
{
protected override IView CreateView(ControllerContext controllerContext, string viewPath, string masterPath)
{
return new RazorView(
controllerContext,
viewPath,
masterPath,
true, //<--- this drives whether to use _ViewStart pages. It was set to false
FileExtensions,
ViewPageActivator
);
}
}
Related
We have an ASP.NET application. We cannot edit source code of controllers. But we can implement ActionFilter.
One of our controller action methods returns JSON. Is it possible to modify it in ActionFilter? We need to add one more property to a returned object.
Maybe, some other way to achieve it?
Found this interesting and as #Chris mentioned, though conceptually I knew this would work, I never tried this and hence thought of giving it a shot. I'm not sure whether this is an elegant/correct way of doing it, but this worked for me. (I'm trying to add Age property dynamically using ActionResult)
[PropertyInjector("Age", 12)]
public ActionResult Index()
{
return Json(new { Name = "Hello World" }, JsonRequestBehavior.AllowGet);
}
And the filter:
public class PropertyInjector : ActionFilterAttribute
{
string key;
object value;
public PropertyInjector(string key, object value)
{
this.key = key;
this.value = value;
}
public override void OnActionExecuted(ActionExecutedContext filterContext)
{
var jsonData = ((JsonResult)filterContext.Result).Data;
JObject data = JObject.FromObject(jsonData);
data.Add(this.key,JToken.FromObject(this.value));
filterContext.Result = new ContentResult { Content = data.ToString(), ContentType = "application/json" };
base.OnActionExecuted(filterContext);
}
}
Update
If it's not dynamic data which is to be injected, then remove filter constructor and hard code key & value directly and then the filter could be registered globally without editing the controller
GlobalFilters.Filters.Add(new PropertyInjector());
I'm building a generic web application for two business groups. The logo/banner needs to be changed based on the querystring. For example, if the url is http://foo.com/test?bg=a it shows the logo for business group a and if the url is http://foo.com/test?bg=b it shows the logo for business group b. This is not a problem if I only had one action. But I have many actions.
I could check the query string on all actions but there must be a nice way to do it. I have an perception that I need to do something with the routing stuff but just don't know how. Can anyone please let me know how to do it?
You can write a Custom Routing Handler and use routing to extract the querystring as a parameter, and pass into RouteData where it can be accessed anywhere.
public class RouteWithQueryStringValueHandler : MvcRouteHandler
{
private readonly string key;
public RouteWithQueryStringValueHandler(string key)
: base()
{
this.key = key;
}
protected override IHttpHandler GetHttpHandler(RequestContext requestContext)
{
var request = requestContext.HttpContext.Request;
var qsValue = requestContext.HttpContext.Request[key];
var router = base.GetHttpHandler(requestContext);
requestContext.RouteData.DataTokens[key] = qsValue;
return router;
}
}
Register as follows:
routes.Add(new Route("{controller}/{action}/{id}",
new RouteValueDictionary(
new { controller = "Home",
action = "Index",
id = UrlParameter.Optional
}),
new RouteWithQueryStringValueHandler("bg")));
Get the logo for Routing data:
var logo = RouteData.DataTokens["bg"];
You could write a custom helper method which based on the query string parameter will append a given class name to some div. Then of course you would have different class definitions in your CSS file applying a background-image.
For example:
public static class HtmlExtensions
{
public static string BannerClass(this HtmlHelper html)
{
var bg = html.ViewContext.Controller.ValueProvider.GetValue("bg");
if (bg == null || string.IsNullOrEmpty(bg.AttemptedValue))
{
// no bg parameter => return a default class
return "default_banner";
}
if (string.Equals("a", bg.AttemptedValue))
{
return "banner_a";
}
else if (string.Equals("b", bg.AttemptedValue))
{
return "banner_b";
}
// unknown value for the bg parameter => return a default class
return "default_banner";
}
}
and then in your _Layout you could apply this class to some placeholder like a div or even the body:
<div class="#Html.BannerClass()">OK</div>
This way it will always be applied for all view in your application.
Now all that's left is to define your CSS rules for the different banners:
.default_banner {
background-image: url('../images/default_banner.png')
}
.banner_a {
background-image: url('../images/banner_a.png')
}
.banner_b {
background-image: url('../images/banner_b.png')
}
If you are using Razor (and I believe this does break the separation of responsibilities guideline) change the _ViewStart.cshtml to do it.
#{
if (/* Context.QueryString Params, not at my development box*/)
{
Layout = "~/Views/Shared/Layout-Group1.cshtml";
}
else
{
Layout = "~/Views/Shared/Layout-Group2.cshtml";
}
}
I prefer this route because it makes any future requests (layout + css + javascript) fairly easy because they can all be updated within the Layout.
Place some code in your master page(s) to make the decision as to which banner to display based on the query string. Ideally the code wouldn't be completely inline i.e. it'd be in a helper class.
I'm currently developing a site using ASP.Net MVC3 with Razor. Inside the "View/Shared" folder, I want to add a subfolder called "Partials" where I can place all of my partial views (for the sake of organizing the site better.
I can do this without a problem as long as I always reference the "Partials" folder when calling the views (using Razor):
#Html.Partial("Partials/{ViewName}")
My question is if there is a way to add the "Partials" folder to the list that .Net goes through when searching for a view, this way I can call my view without having to reference the "Partials" folder, like so:
#Html.Partial("{ViewName}")
Thanks for the help!
Solved this. To add the "Shared/Partials" sub directory I created to the list of locations searched when trying to locate a Partial View in Razor using:
#Html.Partial("{NameOfView}")
First create a view engine with RazorViewEngine as its base class and add your view locations as follows. Again, I wanted to store all of my partial views in a "Partials" subdirectory that I created within the default "Views/Shared" directory created by MVC.
public class RDDBViewEngine : RazorViewEngine
{
private static readonly string[] NewPartialViewFormats =
{
"~/Views/{1}/Partials/{0}.cshtml",
"~/Views/Shared/Partials/{0}.cshtml"
};
public RDDBViewEngine()
{
base.PartialViewLocationFormats = base.PartialViewLocationFormats.Union(NewPartialViewFormats).ToArray();
}
}
Note that {1} in the location format is the Controller name and {0} is the name of the view.
Then add that view engine to the MVC ViewEngines.Engines Collection in the Application_Start() method in your global.asax:
ViewEngines.Engines.Add(new RDDBViewEngine());
Thank you for your answers. This has organized my Shared folder, but why do you create a new type of view engine? I just made a new RazorViewEngine, set it's PartialViewLocationFormats and added it to the list of ViewEngines.
ViewEngines.Engines.Add(new RazorViewEngine
{
PartialViewLocationFormats = new string[]
{
"~/Views/{1}/Partials/{0}.cshtml",
"~/Views/Shared/Partials/{0}.cshtml"
}
});
It´s nice to custom the view engine, but if you just want to have a subfolder por partials you don´t need that much...
Just use the full path to the partial view, as done for the Layout View:
#Html.Partial("/Views/Shared/Partial/myPartial.cshtml")
Hope it helps someone...
If you are doing this in ASP.NET Core, simple go to the Startup class, under ConfigureServices method, and put
services.AddMvc()
.AddRazorOptions(opt => {
opt.ViewLocationFormats.Add("/Views/{1}/Partials/{0}.cshtml");
opt.ViewLocationFormats.Add("/Views/Shared/Partials/{0}.cshtml");
});
I've updated lamarant's excellent answer to include Areas:
public class RDDBViewEngine : RazorViewEngine
{
private static readonly string[] NewPartialViewFormats =
{
"~/Views/{1}/Partials/{0}.cshtml",
"~/Views/Shared/Partials/{0}.cshtml"
};
private static List<string> AreaRegistrations;
public RDDBViewEngine()
{
AreaRegistrations = new List<string>();
BuildAreaRegistrations();
base.PartialViewLocationFormats = base.PartialViewLocationFormats.Union(NewPartialViewFormats).ToArray();
base.PartialViewLocationFormats = base.PartialViewLocationFormats.Union(areaRegistrations).ToArray();
}
private static void BuildAreaRegistrations()
{
string[] areaNames = RouteTable.Routes.OfType<Route>()
.Where(d => d.DataTokens != null && d.DataTokens.ContainsKey("area"))
.Select(r => r.DataTokens["area"].ToString()).ToArray();
foreach (string areaName in areaNames)
{
AreaRegistrations.Add("~/Areas/" + areaName + "/Views/Shared/Partials/{0}.cshtml");
AreaRegistrations.Add("~/Areas/" + areaName + "/Views/{1}/Partials/{0}.cshtml");
}
}
}
Then don't forget to include in your application start:
public class MvcApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
...
ViewEngines.Engines.Add(new RDDBViewEngine());
}
}
You can also update the partialview-location-formats of the registered RazorViewEngine.
Place the below code in Application_Start in Global.asax.
RazorViewEngine razorEngine = ViewEngines.Engines.OfType<RazorViewEngine>().FirstOrDefault();
if (razorEngine != null)
{
string[] newPartialViewFormats = new[] {
"~/Views/{1}/Partials/{0}.cshtml",
"~/Views/Shared/Partials/{0}.cshtml"
};
razorEngine.PartialViewLocationFormats =
razorEngine.PartialViewLocationFormats.Union(newPartialViewFormats).ToArray();
}
You can create register your own view engine that derives from whatever view engine your are using (Webforms/Razor) and specify whatever locations you want in the constructor or just add them to the list of already existing locations:
this.PartialViewLocationFormats = viewLocations;
Then in application start you would add your view engine like so:
ViewEngines.Engines.Add(new MyViewEngineWithPartialPath());
I am writing a VirtualPathProvider to dynamically load my MVC views, which are located in a different directory. I successfully intercept the call before MVC (in FileExists), but in my VirtualPathProvider, I get the raw, pre-routed url like:
~/Apps/Administration/Account/LogOn
Personally, I know that MVC will look for
~/Apps/Administration/Views/Account/LogOn.aspx
and that I should be reading the file contents from
D:\SomeOtherNonWebRootDirectory\Apps\Administration\Views\Account\LogOn.aspx
but I'd rather not hard code the logic to "add the directory named Views and add aspx to the end".
Where is this logic stored and how can I get it into my virtual path provider?
Thanks. Sorry if I'm not being clear.
Edited
You need to make a class that inherits WebFormViewEngine and sets the ViewLocationFormats property (inherited from VirtualPathProviderViewEngine).
The default values can be found in the MVC source code:
public WebFormViewEngine() {
MasterLocationFormats = new[] {
"~/Views/{1}/{0}.master",
"~/Views/Shared/{0}.master"
};
AreaMasterLocationFormats = new[] {
"~/Areas/{2}/Views/{1}/{0}.master",
"~/Areas/{2}/Views/Shared/{0}.master",
};
ViewLocationFormats = new[] {
"~/Views/{1}/{0}.aspx",
"~/Views/{1}/{0}.ascx",
"~/Views/Shared/{0}.aspx",
"~/Views/Shared/{0}.ascx"
};
AreaViewLocationFormats = new[] {
"~/Areas/{2}/Views/{1}/{0}.aspx",
"~/Areas/{2}/Views/{1}/{0}.ascx",
"~/Areas/{2}/Views/Shared/{0}.aspx",
"~/Areas/{2}/Views/Shared/{0}.ascx",
};
PartialViewLocationFormats = ViewLocationFormats;
AreaPartialViewLocationFormats = AreaViewLocationFormats;
}
You should then clear the ViewEngines.Engines collection and add your ViewEngine instance to it.
As SLaks mentioned above, you need to create a Custom View Engine and add your view-finding logic in the FindView method.
public class CustomViewEngine : VirtualPathProviderViewEngine
{
public override ViewEngineResult FindView(ControllerContext controllerContext, string viewName, string masterName, bool useCache)
{
//Set view path
string viewPath = GetCurrentViewPath();
//Set master path (if need be)
string masterPath = GetCurrentMasterPath();
return base.FindView(controllerContext, viewPath, masterPath, useCache);
}
}
In the Application_Start, you can register your View Engine like this:
ViewEngines.Engines.Clear();
ViewEngines.Engines.Add(new CustomViewEngine());
The answer was that MVC was not finding my controller properly. If MVC does in fact find your controller properly, there should be two requests processed by the VirtualPathProvider:
An initial request with the acutal url requested (ie. http://.../Account/LogOn).
A subsequent FileExists check for http://.../Views/Account/LogOn.aspx, after the request in 1. returns false calling FileExists. This actually retuns the aspx content.
I am developing a website in MVC 2.0. I want to change the View folder location in my website. I wanted to keep the views folder inside other folders, When I try to do so i am getting following errors
The view 'Index' or its master was not found. The following locations were searched:
~/Views/Search/Index.aspx
~/Views/Search/Index.ascx
~/Views/Shared/Index.aspx
~/Views/Shared/Index.ascx
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
My Views folder will be in ~/XYZ/ABC/Views instead of ~/Views. Please solve my problem. Will I get any problems If I change the default Views folder location. Do I need to change anything in HTML Helper classes because I don't know anything in MVC as this is my starting project i dont want to risk..Please help me out...
You'll need to create a custom view engine and use that instead. Fortunately you can just inherit from the default one and change the locations on the constructor. Here's a guide to creating your own view engine: http://www.singingeels.com/Articles/Creating_a_Custom_View_Engine_in_ASPNET_MVC.aspx
From the article:
protected void Application_Start()
{
//... other things up here.
// I want to REMOVE the ASP.NET ViewEngine...
ViewEngines.Engines.Clear();
// and then add my own :)
ViewEngines.Engines.Add(new HoTMeaTViewEngine());
}
public class HoTMeaTViewEngine : VirtualPathProviderViewEngine
{
public HoTMeaTViewEngine()
{
// This is where we tell MVC where to look for our files. This says
// to look for a file at "Views/Controller/Action.html"
base.ViewLocationFormats = new string[] { "~/Views/{1}/{0}.html" };
base.PartialViewLocationFormats = base.ViewLocationFormats;
}
}
Check this place out. How to change default view location scheme in ASP.NET MVC?
base.ViewLocationFormats = new string[] {
"~/Views/{1}/{2}/{0}.aspx",
"~/Views/{1}/{2}/{0}.ascx",
"~/Views/Shared/{2}/{0}.aspx",
"~/Views/Shared/{2}/{0}.ascx" ,
"~/Views/{1}/{0}.aspx",
"~/Views/{1}/{0}.ascx",
"~/Views/Shared/{0}.aspx",
"~/Views/Shared/{0}.ascx"
Even easier is this one Can I specify a custom location to “search for views” in ASP.NET MVC?
As an alternative, you can override the view engine locations for a specific controller without affecting the view engines for the other controllers.
These are some snippets from a product I am developing, but it shows the constructor for one of my controllers, and a view engine I made specificially for controllers that inherit from KBRenderMvcController.
So any controller based off KBRenderMvcController will also have my view engine.
However at no point did I clear the view engine collection, which is relevant. Because I wanted the views my product is using to fall back to default locations.
In short, if you delete \App_plugins\Product\Views\MyView And instead create a \Views\MyView it will still render from \Views\MyView instead.
Also in the ViewEngine I demonstrate code that determines the type of controller being used and if it's not a target controller I return empty view locations so they don't get used for other controllers.
#region Constructor
public KBRenderMvcController()
: base()
{
viewEngine = new KBFrontEndViewEngine();
if (!this.ViewEngineCollection.Contains(viewEngine))
this.ViewEngineCollection.Insert(0, viewEngine);
}
#endregion
public class KBFrontEndViewEngine : RazorViewEngine
{
#region Fields
private static bool _Initialized = false;
private static string[] viewLocationFormats = null;
private static string[] partialViewLocationFormats = null;
private static string[] viewEngineFileExtensions = new string[] { "cshtml" };
#endregion
#region Constructor
public KBFrontEndViewEngine()
{
if (!_Initialized)
{
viewLocationFormats = new string[]
{
string.Concat(KBApplicationCore.PluginRelUrl, "/Views/{1}/{0}.cshtml"),
string.Concat(KBApplicationCore.PluginRelUrl, "/Views/Partials/{0}.cshtml")
};
partialViewLocationFormats = new string[]
{
string.Concat(KBApplicationCore.PluginRelUrl, "/Views/{1}/Partials/_partial{0}.cshtml"),
string.Concat(KBApplicationCore.PluginRelUrl, "/Views/Partials/_partial{0}.cshtml"),
string.Concat(KBApplicationCore.PluginRelUrl, "/Views/{1}/Dialogs/_dialog{1}.cshtml"),
string.Concat(KBApplicationCore.PluginRelUrl, "/Views/Dialogs/_dialog{1}.cshtml"),
};
_Initialized = true;
}
base.ViewLocationFormats = viewLocationFormats;
base.PartialViewLocationFormats = partialViewLocationFormats;
base.MasterLocationFormats = viewLocationFormats;
base.FileExtensions = viewEngineFileExtensions;
}
#endregion
#region Methods
//Don't run on requests that are not for our hijacked controllers
public override ViewEngineResult FindPartialView(ControllerContext controllerContext, string partialViewName, bool useCache)
{
Type controllerType = controllerContext.Controller.GetType();
Type baseType = controllerType.BaseType;
if ((baseType != null) && (baseType.Name == "KBRenderMvcController`1") || (baseType.Name == "KBFrontEndBaseSurfaceController"))
return base.FindPartialView(controllerContext, partialViewName, useCache);
else
return new ViewEngineResult(new List<string>());
}
#endregion
}