Simple example of integrating with ChatGPT API from .NET

ChatGPTAPIExample.cs

using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;
using System.Text;
using System.Text.Json;

namespace Samples;

public class ChatGPTAPIExample(ILogger<ChatGPTAPIExample> logger, IConfiguration configuration)
{
    private string Prompt = "Please explain the following code :";
    private string CouldNotLoadDescription = "ChatGPT description could not be loaded";

    public async Task<string> ExplainCodeAsync(string codeSnippet)
    {
        // Get a key from : https://platform.openai.com/api-keys
        var ApiKey = configuration["ChatGPT:APIKey"];

        var ApiUrl = "https://api.openai.com/v1/chat/completions";
        var Model = "gpt-4-turbo-preview";
        var Temperature = 0.3;

        var messages = new[]
        {
            new { role = "user", content = $"{Prompt}\n\n{codeSnippet}" }
        };

        var data = new
        {
            model = Model,
            messages,
            temperature = Temperature
        };

        var HttpClient = new HttpClient();

        HttpClient.DefaultRequestHeaders.Add("Authorization", $"Bearer {ApiKey}");

        var json = JsonSerializer.Serialize(data);

        var requestContent = new StringContent(json, Encoding.UTF8, "application/json");

        try
        {
            var response = await HttpClient.PostAsync(ApiUrl, requestContent);

            if (response.IsSuccessStatusCode)
            {
                var responseContent = await response.Content.ReadAsStringAsync();
                
                using var doc = JsonDocument.Parse(responseContent);
                var choicesElement = doc.RootElement.GetProperty("choices");
                var messageObject = choicesElement[0].GetProperty("message");
                var content = messageObject.GetProperty("content").GetString();

                if (content is not null)
                {
                    return content;
                }
                else
                {
                    logger.LogError("ChatGPT API response did not contain expected content");
                    return CouldNotLoadDescription;
                }
            }
            else
            {
                logger.LogError("ChatGPT API request failed with status code: {StatusCode}", response.StatusCode);
                return CouldNotLoadDescription;
            }
        }
        catch (Exception ex)
        {
            logger.LogError(ex, "ChatGPT error occurred: {Message}", ex.Message);
            return CouldNotLoadDescription;
        }
    }
}