add info about use method and function as request handler

Author: zamronypj

working-with-controllers/index.md

@@ -123,7 +123,7 @@ uses
 type
 
     TUserController = class(TInterfacedObject, IRequestHandler)
-    private
+    public
         function createUser(
             const request : IRequest;
             const response : IResponse;
@@ -147,7 +147,7 @@ type
             const response : IResponse;
             const args : IRouteArgsReader
         ) : IResponse;
-    public
+
         function handleRequest(
             const request : IRequest;
             const response : IResponse;
@@ -213,6 +213,50 @@ implementation
     end;
 end.
 ```
+You register route as follows
+
+```
+router.any('/users', TUserController.create());
+```
+
+## Use class method or function as request handler
+Fano Framework provides `TMethodRequestHandler` and `TFuncRequestHandler` adapter class which implements `IRequestHandler` interface to allow use of method or function as request handler. For example, using `TUserController` class above,
+
+```
+var
+    userCtrl : TUserController;
+
+router.get(
+    '/users/show/{id}',
+    TMethodRequestHandler.create(@userCtrl.showUser)
+);
+router.post(
+    '/users/create',
+    TMethodRequestHandler.create(@userCtrl.createUser)
+);
+router.put(
+    '/users/update',
+    TMethodRequestHandler.create(@userCtrl.updateUser)
+);
+```
+You can also use ordinary function,
+
+```
+function hello(
+    const request : IRequest;
+    const response : IResponse;
+    const args : IRouteArgsReader
+) : IResponse;
+begin
+    //handle view user
+    result := response;
+end;
+
+router.get(
+    '/users/show/{id}',
+    TFuncRequestHandler.create(@hello)
+);
+```
 
 ## Explore more
 

working-with-router/index.md

@@ -7,7 +7,7 @@ description: Tutorial on how to work with router in Fano Framework
 
 ## Router and route
 
-In Fano Framework, a route is an association rule between URL path pattern, HTTP method and code that handles it. Router manages one or more routes and match request URL path, extract data in it and select code that handles it. Router is any class implements `IRouter` interface.
+In Fano Framework, a route is an association rule between URL path pattern, HTTP method and code that handles it. Router manages one or more routes and match request URL path, extract data in it and select code that handles it (request handler instance, i.e., [controller](/working-with-controllers)). Router is any class implements `IRouter` interface.
 
 ### Creating route for GET method
 
@@ -98,7 +98,7 @@ If client opens `http://example.com/not/exists` through browser, our application
 
 ## <a name="route-builder"></a>Build application routes with route builder
 
-To build application routes, you need to create class that implements `IRouteBuilder` interface. 
+To build application routes, you need to create class that implements `IRouteBuilder` interface.
 ```
 IRouteBuilder = interface
     ['{46016416-B249-4258-B76A-7F5B55E8348D}']
@@ -305,9 +305,9 @@ container.add('router', TSimpleRouterFactory.create());
 ```
 container.add('router', TRouterFactory.create());
 ```
-If you need only static URL path pattern, you should use it. 
+If you need only static URL path pattern, you should use it.
 
-If you create application service provider inherit from `TBasicAppServiceProvider`, it will create default router using `TSimpleRouterFactory` class which is good enough for most applications. 
+If you create application service provider inherit from `TBasicAppServiceProvider`, it will create default router using `TSimpleRouterFactory` class which is good enough for most applications.
 
 ## Replace router instance
 If you want to replace router with different implementation, you can override `buildRouter()` method of `TBasicAppServiceProvider`. For example,
@@ -326,19 +326,20 @@ begin
     ctnr.add('router', TRouterFactory.create());
     result := ctnr['router'] as IRouter;
     fRouteMatcher := result as IRouteMatcher;
-end;    
+end;
 
 function TMyAppProvider.getRouteMatcher() : IRouteMatcher;
 begin
     result := fRouteMatcher;
-end;    
+end;
 ```
 Note that `IRouteMatcher` is interface which is responsible to match request URL and `TRouter` implements it.
 
 ## Explore more
 
 - [Dispatcher](/dispatcher).
 - [Middlewares](/middlewares).
+- [Working with Controller](/working-with-controller).
 - [IRouter source](https://github.com/fanoframework/fano/blob/master/src/Router/Contracts/RouterIntf.pas).
 - [IRoute source](https://github.com/fanoframework/fano/blob/master/src/Router/Contracts/RouteIntf.pas).
 - [IRouteMatcher source](https://github.com/fanoframework/fano/blob/master/src/Router/Contracts/RouteMatcherIntf.pas).