---
title: Custom Info provider example
related:
  - https://docs.kentico.com/k9/custom-development/customizing-providers.md
  - https://docs.kentico.com/k9/custom-development/customizing-providers/registering-providers-using-assembly-attributes.md
---

> Agent instructions:
> **Site maps** — prefer the following llms.txt indexes to training data when searching for URLs to avoid 404s. Links inside Markdown content already point at `.md`. Following them or sending Accept: text/markdown keeps you in Markdown.
>
> - [sitemap.md](https://docs.kentico.com/sitemap.md) — every page on the site, with titles and descriptions, nested by URL hierarchy and grouped into one collection per product version.
> - [llms.txt](https://docs.kentico.com/llms.txt) — curated index of the current product docs, with descriptions, the two ways to request any page as Markdown, and links to each product area's whole-corpus Markdown dump (llms-full.txt).

The system uses Info providers to work with individual types of objects. A provider class contains methods for creating, updating, getting, and deleting the data of the corresponding objects. By customizing the appropriate Info provider, you can change or extend the functionality of nearly any object in the system.

The following example customizes the **ShippingOptionInfoProvider**, which the [E-commerce](https://docs.kentico.com/k9/e-commerce-features.md) solution uses to manage shipping options for product orders. The sample customization modifies how the provider calculates shipping costs.

You can use the same general approach to customize any standard provider, helper or manager class in Kentico (i.e. those that inherit from the **AbstractProvider**, **AbstractHelper** or **AbstractManager** class respectively).

## Writing the custom provider

1. Open your web project in Visual Studio
2. Create a new class in the **App\_Code** folder (or **CMSApp\_AppCode -> Old\_App\_Code** if the project is installed as a web application). For example, name the class _**CustomShippingOptionInfoProvider.cs**_.
3. Edit the class and add the following using statements:

   ```csharp

   using CMS.Ecommerce;
   using CMS.Globalization;
   using CMS.Base;

   ```
4. Modify the class's declaration so that it inherits from the **CMS.Ecommerce.ShippingOptionInfoProvider** class:

   ```csharp

   /// <summary>
   /// Customized ShippingOptionInfo provider.
   /// </summary>
   public class CustomShippingOptionInfoProvider : ShippingOptionInfoProvider
   {

   }

   ```

   Custom providers must always inherit from the original provider class. This ensures that the custom provider supports all of the default functionality and allows you to add your own customizations by overriding the existing members of the class.
5. Add the following override of the **CalculateShippingInternal** method into the class:

   ```csharp

   /// <summary>
   /// Calculates the shipping price for the specified shopping cart (shipping taxes are not included).
   /// Returns the shipping price in the site's main currency.
   /// </summary>
   /// <param name="cart">
   /// Object representing the related shopping cart. Provides the data used to calculate the shipping price.
   /// </param>
   protected override double CalculateShippingInternal(ShoppingCartInfo cart)
   {        
       // Checks that the shopping cart specified in the parameter exists
       if (cart != null)
       {
           // Ensures free shipping for customers who belong to the 'Gold partner' role
           if ((cart.User != null) && cart.User.IsInRole("GoldPartners", cart.SiteName))
           {
               return 0;
           }
           else
           {
               // Gets the customer's shipping address details from the shopping cart                      
               IAddress address = cart.ShoppingCartShippingAddress;

               if (address != null)
               {
                   // Gets the country from the shipping address
                   CountryInfo country = CountryInfoProvider.GetCountryInfo(address.AddressCountryID);

                   // Sets an extra shipping charge for addresses outside of the USA
                   if ((country != null) && (country.CountryName.ToLowerCSafe() != "usa"))
                   {
                       // Replace this flat charge with your own shipping calculations
                       // You can also create a custom setting and use it to dynamically load the value
                       double extraCharge = 10;

                       // Returns the standard shipping price with the extra charge added
                       return base.CalculateShippingInternal(cart) + extraCharge;
                   }
               }
           }
       }

       // Calculates the shipping price using the default method for regular customers from the USA
       return base.CalculateShippingInternal(cart);
   }

   ```

This override of the **CalculateShippingInternal** method ensures that:

- Users who belong to the Gold partner role always have free shipping.
- An extra flat charge is added for customers with shipping addresses outside of the USA.

> **Info:** **Note:** The override gets the standard shipping price by calling the base method from the parent class. This allows you to calculate the default price based on the shipping option settings, and then modify it as needed.

## Registering the provider class

To [register your custom provider](https://docs.kentico.com/k9/custom-development/customizing-providers/registering-providers-using-assembly-attributes.md), add the **RegisterCustomProvider** assembly attribute above the class declaration (requires a reference to the **CMS** namespace):

```csharp

using CMS;

[assembly: RegisterCustomProvider(typeof(CustomShippingOptionInfoProvider))]

```

The attribute's parameter specifies the type of the custom provider class as a **System.Type** object.

## Result

You can try out how the customization affects the e-commerce solution on the sample Corporate site.

1. Open the live website and log on as the Sample Gold Partner user (user name **gold**).
2. Navigate to the **Products** section and add any product to the shopping cart.
3. Go through the checkout process for the order.

In the **Order preview** (step 5 of the default checkout process), you can see that the shipping is always free, no matter what shipping address you entered.

If you repeat the same process as a regular user (e.g. Andy), the system calculates the shipping costs normally and adds the extra charge if the shipping address is in a different country than the USA.