Routing web api

Routing is how Web API matches a URI to an action

Web API used convention-based routing

https://github.com/api2/github/iamchamith/BestPractices/blob/master/Test.ts

[RoutePrefix("api2")]
   public class RoutingExampleController : ApiController
   { 
       [Route("github/{user}/{repo}/blob/master/{file}")]
       public string GetFile(string user,string repo,string file) {
 
           return $"{user}-> {repo}->{file}";
       }
   }

github is must

Route Constraints

[Route("user/{id:int}")]
       public string GetUser(int id)
       {
 
           return "Chamith " + id;
       }

Constraint	Description	Example
alpha	Matches uppercase or lowercase Latin alphabet characters (a-z, A-Z)	{x:alpha}
bool	Matches a Boolean value.	{x:bool}
datetime	Matches a DateTime value.	{x:datetime}
decimal	Matches a decimal value.	{x:decimal}
double	Matches a 64-bit floating-point value.	{x:double}
float	Matches a 32-bit floating-point value.	{x:float}
guid	Matches a GUID value.	{x:guid}
int	Matches a 32-bit integer value.	{x:int}
length	Matches a string with the specified length or within a specified range of lengths.	{x:length(6)} {x:length(1,20)}
long	Matches a 64-bit integer value.	{x:long}
max	Matches an integer with a maximum value.	{x:max(10)}
maxlength	Matches a string with a maximum length.	{x:maxlength(10)}
min	Matches an integer with a minimum value.	{x:min(10)}
minlength	Matches a string with a minimum length.	{x:minlength(10)}
range	Matches an integer within a range of values.	{x:range(10,50)}
regex	Matches a regular expression.	{x:regex(^\d{3}-\d{3}-\d{4}$)}

Optional URI Parameters and Default Values

Default parameter

public class BooksController : ApiController
{
    [Route("api/books/locale/{lcid:int?}")]
    public IEnumerable<Book> GetBooksByLocale(int lcid = 1033) { ... }
}

Url parameter

public class BooksController : ApiController
{
    [Route("api/books/locale/{lcid:int=1033}")]
    public IEnumerable<Book> GetBooksByLocale(int lcid) { ... }
}

Init routing in application startup 
inside Globle.asax

protected void Application_Start()
        {
            RouteConfig.RegisterRoutes(RouteTable.Routes);
        }

Using router table

public static class WebApiConfig
    {
        public static void Register(HttpConfiguration config)
        {

          // Web API routes
           config.MapHttpAttributeRoutes();
 
           config.Routes.MapHttpRoute(
               name: "DefaultApi",
               routeTemplate: "api/{controller}/{action}/{id}",
               defaults: new { id = RouteParameter.Optional }
           );
     }
}