### Quick Start: Braintree Gateway Transaction Sale

Source: https://github.com/braintree/braintree_dotnet/blob/master/README.md

This example demonstrates how to initialize the Braintree Gateway in sandbox mode and process a transaction sale using a payment method nonce. It includes error handling for successful transactions and various failure scenarios.

```csharp
using System;
using Braintree;

namespace BraintreeExample
{
    class Program
    {
        static void Main(string[] args)
        {
            var gateway = new BraintreeGateway
            {
                Environment = Braintree.Environment.SANDBOX,
                MerchantId = "the_merchant_id",
                PublicKey = "a_public_key",
                PrivateKey = "a_private_key"
            };

            TransactionRequest request = new TransactionRequest
            {
                Amount = 1000.00M,
                PaymentMethodNonce = nonceFromTheClient,
                Options = new TransactionOptionsRequest
                {
                    SubmitForSettlement = true
                }
            };

            Result<Transaction> result = gateway.Transaction.Sale(request);

            if (result.IsSuccess())
            {
                Transaction transaction = result.Target;
                Console.WriteLine("Success!: " + transaction.Id);
            }
            else if (result.Transaction != null)
            {
                Transaction transaction = result.Transaction;
                Console.WriteLine("Error processing transaction:");
                Console.WriteLine("  Status: " + transaction.Status);
                Console.WriteLine("  Code: " + transaction.ProcessorResponseCode);
                Console.WriteLine("  Text: " + transaction.ProcessorResponseText);
            }
            else
            {
                foreach (ValidationError error in result.Errors.DeepAll())
                {
                    Console.WriteLine("Attribute: " + error.Attribute);
                    Console.WriteLine("  Code: " + error.Code);
                    Console.WriteLine("  Message: " + error.Message);
                }
            }
        }
    }
}
```

--------------------------------

### Build and Test with .NET CLI on Windows

Source: https://github.com/braintree/braintree_dotnet/blob/master/DEVELOPMENT.md

Restore dependencies, build the project, and run tests using the dotnet CLI on a Windows environment.

```bash
dotnet restore
dotnet build
dotnet test .
```

--------------------------------

### Build Docker Image with .NET Core 3.1

Source: https://github.com/braintree/braintree_dotnet/blob/master/DEVELOPMENT.md

Use this command to build a Docker image with .NET Core 3.1 for development.

```bash
make core3
```

--------------------------------

### Build Docker Image with Mono

Source: https://github.com/braintree/braintree_dotnet/blob/master/DEVELOPMENT.md

Use this command to build a Docker image that includes Mono for development.

```bash
make mono
```

--------------------------------

### Restore Dependencies for .NET Core 3.1 Tests

Source: https://github.com/braintree/braintree_dotnet/blob/master/DEVELOPMENT.md

Restore project dependencies before running tests on a Unix-like system with .NET Core 3.1.

```bash
dotnet restore
dotnet test . -f netcoreapp3.1
```

--------------------------------

### Conditional Compilation for Cross-Compatibility

Source: https://github.com/braintree/braintree_dotnet/blob/master/DEVELOPMENT.md

Use preprocessor directives to conditionally compile code for .NET Core and .NET Framework environments. Ensure methods are available in both target frameworks.

```csharp
#if netcore
NetCore.Method();
#else
NetFramework.Method();
#end
```

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