How to integrate Web API ?

 [VGAuthorize(Roles = "Admin")]
 public class ProductionController : ApiController
 {
     Product[] products = new Product[]
     {
     new Product { Id = 1, Name = "Tomato Soup", Category = "Groceries", Price = 1 },
     new Product { Id = 2, Name = "Yo-yo", Category = "Toys", Price = 3.75M },
     new Product { Id = 3, Name = "Hammer", Category = "Hardware", Price = 16.99M }
     };

     [VGAuthorize(Permissions = "CanGetAllRoles", Roles = "RoleManager")]
     public IEnumerable<Product> GetAllProducts()
     {
         return products;
     }

     [VGAuthorize(Permissions = "ReadOnly")]
     [VGAuthorize(Permissions = "CanGetById")]
     public Product GetProductById(int id)
     {
         var product = products.FirstOrDefault((p) => p.Id == id);
         if (product == null)
         {
             throw new HttpResponseException(HttpStatusCode.NotFound);
         }
         return product;
     }
}

[VB.NET]
<VGAuthorize(Roles:="Admin")> _
Public Class ProductionController
    Inherits ApiController
    Private products As Product() = New Product() {New Product() With { _
        .Id = 1, _
        .Name = "Tomato Soup", _
        .Category = "Groceries", _
        .Price = 1 _
    }, New Product() With { _
        .Id = 2, _
        .Name = "Yo-yo", _
        .Category = "Toys", _
        .Price = 3.75D _
    }, New Product() With { _
        .Id = 3, _
        .Name = "Hammer", _
        .Category = "Hardware", _
        .Price = 16.99D _
    }}

    <VGAuthorize(Permissions:="CanGetAllRoles", Roles:="RoleManager")> _
    Public Function GetAllProducts() As IEnumerable(Of Product)
        Return products
    End Function

    <VGAuthorize(Permissions:="ReadOnly")>
    <VGAuthorize(Permissions:="CanGetById")> _
    Public Function GetProductById(id As Integer) As Product
        Dim product = products.FirstOrDefault(Function(p) p.Id = id)
        If product Is Nothing Then
            Throw New HttpResponseException(HttpStatusCode.NotFound)
        End If
        Return product
    End Function 
End Class