View Engine View engine (2)

Before getting started, let's take a look at the usage of the Params Keyword:

Params

ParamsYou can specify the parameter when the number of parameters is variable.

1. In the method declarationParamsNo other parameters are allowed after the keyword, and only one parameter is allowed in the method declaration.ParamsKeywords

 

First, customize the view

 1    Public   Class  Debugview: iview  2   {  3           Public   Void  Render (viewcontext, system. Io. textwriter writer) 4   {  5 Write (writer, "  ----- Routedata ------  "  );  6               Foreach ( String Key In  Viewcontext. routedata. Values. Keys)  7   {  8 Write (writer,"  Key: {0} value: {1}  "  , Key, viewcontext. routedata. Values [Key]);  9   }  10   11 Write (writer, "  -------- View data --------  "  )  12               Foreach ( String KeyIn  Viewcontext. viewdata. Keys)  13   {  14 Write (writer, "  Key: {0}, value: {1}  "  , Key, viewcontext. viewdata [Key]);  15   }  16   }  17   18           Private  Void Write (textwriter writer, String Template, Params   Object  [] Values)  19   {  20 Writer. Write ( String . Format (template, values) + "  <P/>  "  );  21   } 22 }

Then, create a view Engine

 1   Public   Class  Debugviewengine: iviewengine  2   {  3           Public Viewengineresult findpartialview (controllercontext, String Partialviewname, Bool  Usecache)  4   { 5               Return   New Viewengineresult ( New   String [] { "  Debug data view Engine  "  });  6   }  7   8           Public Viewengineresult findview (controllercontext, String Viewname,String Mastername, Bool  Usecache)  9   {  10               If (Viewname = "  Debugdata  "  )  11   {  12                   Return   New Viewengineresult (New Debugview (), This  );  13   }  14               Else  15   {  16                   Return   New Viewengineresult ( New   String [] { "  Debug data view Engine "  });  17   }  18   }  19   20           Public   Void  Releaseview (controllercontext, iview view)  21   {  22               Throw   New Notimplementedexception ();  23   }  24 }

Finally, register the view engine:

1 Protected VoidApplication_start (){2 Arearegistration. registerallareas ();3Viewengines. Engines. Add (NewDebugdataviewengine ());4 Registerglobalfilters (globalfilters. filters );5 Registerroutes (routetable. routes );6}
 

Here, the same applicationProgramMultiple View engines are supported. If multiple view engines support the same view, only the first view engine is displayed in the set order. Therefore, if you want to prioritize a view engine, the best way is to place it in the first place.

Viewengines. Engines. insert (0, new debugdataviewengine ());

Next we can perform the test:

Create a homecontroller and write the followingCode:

 1    Public   Class  Homecontroller: Controller  2   {  3           //  4           //  Get:/home/  5   6           Public  Viewresult index () 7   {  8 Viewdata [ "  Message  " ] = "  Hello New View Engine  "  ;  9 Viewdata [ "  Time  " ] = Datetime. Now. tow.datestring (); 10               Return View ( "  Debugdata  "  );  11   }  12   13 }

Run to view the running results:

 

Here, we have created a custom view. The next article will explain how to use the built-in razor view.