The EpicPay Gateway C# SDK can help you get a quick start when working with the EpicPay Gateway Payments API.

This SDK was written against .Net Standard 2.0, and as such should work against most modern compliant .Net implementations, including .Net Core > 2.0 and .Net Framework > 4.6.1.

Before starting with the SDK, you will need to create an API key online at https://secure.epicpay.com/merchant/. For up-to-date documentation on this process, please refer to our online documentation.

Open the EpicGatewaySDK solution in Visual Studio 2017 or newer (also tested in VS2019). The solution and project are already configured to build the SDK into a .nupkg. Before building, consider whether you wish to build the SDK in debug or release mode. After building the SDK, (Build->Build Solution or Ctrl-Shift-B) the package should be present in SDK root directory/Epic.GatewaySDK/bin/Debug or release/.

To install the .nupkg, place it in a directory on your drive that is defined as a package source in NuGet. To add a new directory as a package source, go to Tools->Options->Nuget Package Manager->Package Sources. Once you have added the source, you should be able to install Epic.GatewaySDK from the NuGet package manager. (You may have to select your local package source in the top-right of the package manager GUI).

To start, you'll need to instantiate an instance of the EpicGateway class from the Epic.GatewaySDK namespace. The constructor has three parameters:

• APIKey: The API Key ID
• Password: The API Key Password
• BaseURL: The API base URL with a trailing slash.

The API base URL will vary depending on whether you are working against the sandbox or the live production environment.

using Epic.GatewaySDK;
// ...
    EpicGateway gateway;
    gateway = new EpicGateway("apikey", "apipassword", "https://sandbox-api.epicpay.com/payment/v1/");
// ...

All interactions with the API will be handled through the instance of the EpicGateway object you created here, from authentication to asynchronous HTTP requests.

All methods and models within the SDK have an analogous relationship to the methods and object structures defined by the EpicPay Gateway API Specification. If you ever need clarification on how a method works, what parameters it requires, or what are valid for those parameters, the API specification is the best source for that information.

Although the SDK mostly mirrors the API's structure, there are a few subtle differences in how each are used:

• The TransactionType field does not need to be set manually on any transactions. Instead, there are dedicated methods to call for each transaction type.
• BillingAddress and CustomerAddress fields both have the class Address. This has no functional difference beyond naming.

Each of the public methods exposed by the EpicGateway class corresponds to one of the methods or transaction types you can send to the Payment API. You will likely want to reference the API documentation when crafting your requests for the first time.

You'll find all the request and response models for this SDK in the namespace Epic.GatewaySDK.Models. Each request takes as input its own request object type, such as a SaleRequest. As such, submitting a request looks something like this:

SaleRequest request = new SaleRequest
{
    Amount = 111,
    Currency = "usd",
    Method = "credit_card",
    CreditCard = new CreditCard
    {
        CardNumber = "****1111",
        CardHolderName = "John Smith",
        ExpMonth = "01",
        ExpYear = "22",
        CVV = "456"
    },
    BillingAddress = new BillingAddress()
    {
        FirstName = "Mary",
        LastName = "Smith",
        Address = "1 Main St.",
        Address2 = "Suite 201",
        City = "Burlington",
        CompanyName = "Big Company",
        StateProvince = "MA",
        PostalCode = "01803-3747",
        Email = "person@example.com",
        CountryCode = "US",
        Phone = new Phone { Number = "2015551255", Type = "mobile" }
    }
};
SaleResponse response = await _gw.Sale(request);

The EpicPay Gateway C# SDK only throws exceptions for network-related errors, and does not throw exceptions for errors returned by the API. Instead, you will need to check for errors returned by the API by inspecting Status.ResponseCode in the response object itself.

Check the API documentation for info on the different kinds of Response Codes and Reason Codes you can receive.

Check the ReasonText field for more information on any errors you encounter.