Integrating an Online Payment Gateway in ASP.NET using ADO.NET

Integrating an online payment gateway into your ASP.NET application using ADO.NET is a crucial task for enabling secure and seamless transactions on your website. This guide will walk you through the steps to set up, integrate, and handle responses from a payment gateway.

Step 1. Set up Payment Gateway account

Before you can integrate a payment gateway, you need to register with the payment gateway provider. Here’s how you can do it:

Register with the Payment Gateway Provider

  1. Choose a Payment Gateway Provider: Research and choose a reliable payment gateway provider that suits your business needs. Popular options include PayPal, Stripe, Razorpay, etc.
  2. Sign Up for an Account
    • Visit the provider’s website and sign up for a merchant account.
    • Fill in the required details such as business information, contact details, and banking information.
  3. Complete the Verification Process
    • The provider may require you to verify your identity and business details. This usually involves submitting documents like a business license, tax identification number, and proof of identity.
  4. Obtain API Credentials
    • Once your account is approved, you will receive the necessary API credentials such as Merchant ID, Access Code, and Secret Key. These credentials are essential for integrating the payment gateway with your website.

Step 2. Create a Payment Form

Create an HTML form to collect payment details from the user and submit them to the payment gateway. Below is a sample payment form:

<form method="post" action="https://www.paymentgateway.com/process">
    <input type="hidden" name="merchant_id" value="your_merchant_id">
    <input type="hidden" name="order_id" value="your_order_id">
    <input type="hidden" name="amount" value="your_amount">
    <input type="hidden" name="currency" value="INR">
    <input type="hidden" name="redirect_url" value="https://www.yourwebsite.com/payment-response">
    <input type="hidden" name="cancel_url" value="https://www.yourwebsite.com/payment-cancel">
    <!-- Add other necessary fields required by the payment gateway -->
    <input type="submit" value="Pay Now">
</form>

Step 3. Redirect to Payment Gateway

When the form is submitted, it redirects to the payment gateway's URL to process the payment.

Step 4. Handle Payment Response

After the payment is processed, the payment gateway redirects the user back to your website with the payment status. You need to handle this response and update your database accordingly.

Create a Handler for Payment Response

Create a new ASP.NET page (e.g., PaymentResponse.aspx) to handle the response.

using System;
using System.Data.SqlClient;
using System.Configuration;
using System.Web.UI;
public partial class PaymentResponse : Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        string orderId = Request.Form["order_id"];
        string amount = Request.Form["amount"];
        string status = Request.Form["status"];
        string transactionId = Request.Form["transaction_id"];   
        // Validate the response (e.g., verify signature)  
        // Save the payment response to the database
        SavePaymentResponse(orderId, amount, status, transactionId);
    }
    private void SavePaymentResponse(string orderId, string amount, string status, string transactionId)
    {
        string connectionString = ConfigurationManager.ConnectionStrings["YourConnectionString"].ConnectionString;
        using (SqlConnection con = new SqlConnection(connectionString))
        {
            string query = "INSERT INTO PaymentResponses (OrderId, Amount, Status, TransactionId) VALUES (@OrderId, @Amount, @Status, @TransactionId)";
            using (SqlCommand cmd = new SqlCommand(query, con))
            {
                cmd.Parameters.AddWithValue("@OrderId", orderId);
                cmd.Parameters.AddWithValue("@Amount", amount);
                cmd.Parameters.AddWithValue("@Status", status);
                cmd.Parameters.AddWithValue("@TransactionId", transactionId);
                con.Open();
                cmd.ExecuteNonQuery();
                con.Close();
            }
        }
    }
}

Step 5. Update your database

Based on the payment status received, update your database to reflect the payment outcome.

Important Considerations

  1. Security: Ensure all data transmitted between your website and the payment gateway is encrypted using HTTPS.
  2. Validation: Validate all responses from the payment gateway, including checking signatures or hashes to ensure data integrity.
  3. Error Handling: Implement robust error handling to manage different payment statuses like success, failure, and pending.
  4. Testing: Test the integration thoroughly in a sandbox environment provided by the payment gateway before going live.

By following these steps, you can successfully integrate a payment gateway into your ASP.NET application, providing a secure and reliable payment experience for your users.