c# - System.NullReferenceException creating viewModel -

so, i'm trying find umbraco node (as ipublishedcontent), , pass viewmodel (as Ш've hijacked route). put in controller:

private addcouponcodesviewmodel viewmodel; public addcouponcodescontroller(){     //get ipublished content     ipublishedcontent content = umbraco.typedcontent(1225);     //pass viewmodel     viewmodel = new addcouponcodesviewmodel(content);     routedata.datatokens["umbraco"] = content; } public actionresult index() {     //return view etc } 

but i'm getting

exception details: system.nullreferenceexception:  object reference not set instance of object. 

here:

 source error(addcouponcodesviewmodel.cs):   line 20:   line 21:         }  line 22:         public addcouponcodesviewmodel(ipublishedcontent content)  line 23:             : base(content)  line 24:         { 

addcouponcoderendermodel.cs:

public class addcouponcodesviewmodel : rendermodel     {     public string test { get; set; }     public list<string> tables { get; set; }     public list<string> errors { get; set; }      public addcouponcodesviewmodel(ipublishedcontent content, cultureinfo culture) : base(content, culture)     {      }     public addcouponcodesviewmodel(ipublishedcontent content)         : base(content)     {      } 

and global.asax

public class global : umbracoapplication {     protected override void onapplicationstarted(object sender, eventargs e)     {         base.onapplicationstarted(sender, e);          bundleconfig.registerbundles(bundletable.bundles);         //arearegistration.registerallareas();         //webapiconfig.register(globalconfiguration.configuration);         //filterconfig.registerglobalfilters(globalfilters.filters);         //routeconfig.registerroutes(routetable.routes);          base.onapplicationstarting(sender, e);          routetable.routes.maproute(         "addcouponcodes",                                              // route name         "admin/{controller}/{action}/{id}",                           // url parameters         new { controller = "addcouponcodes", action = "index", id = "" }  // parameter defaults          );       }  } 

the content published (i've checked , double checked), , node id correct.

what i'm trying here, route example.com/admin/{controller}/{action}/{parameter} routed, having problems connecting umbraconode (and class rendermodel requires ipublishcontent object parameter, i'm in no luck when trying pass anything)

could please me here, been stuck way many hours on :-(

to clarify, if hijacking route, means overriding way umbraco passes it's rendermodel 1 of it's published pages. can either globally overriding main rendermvccontroller, or can override on documenttype-specific basis. example, if have homepage doc type, create:

public homepagecontroller : rendermvccontroller {     public override actionresult index(rendermodel model)     {         // create new rendermodel here, inheriting         // rendermodel          return currenttemplate(rendermodel);     } } 

this route calls homepage through 1 action. this, don't need define new routes in route table. , should override render model in action not in constructor.

your question confusing , it's not entirely clear trying achieve because:

• you have defined route, and
• in constructor calling umbraco.typedcontent(1225) retrieve specific published node

so ... if admin page trying route has been published umbraco (and doesn't sound has), create new controller name of page's document type , override render model in way described above.

however ... if admin page hasn't been published umbraco , want admin page access node data, have couple of options:

• create surface controller, inheriting surfacecontroller. give access umbraco context et al; or
• create standard controller (preferrably in area) , inject contentcache using autofac

e.g.:

builder.registercontrollers(typeof (admincontroller).assembly)        .withparameter("contentcache", umbracocontext.current.contentcache); 

• create standard controller (preferrably in area) , access node using umbraco's contentservice api, i.e. new umbraco.core.services.contentservice().getbyid(1225)

the difference between last 2 approaches that:

• injecting contentcache provides readonly quick access published content.
• accessing contentservice provides read/write access nodes @ expense of speed querying database directly.

it depends on requirement is.

either way, worth taking time read through documentation hijacking umbraco routes, , @ least trying understand going on.