How to Call OpenAI's ChatGPT API from a C# Application?

 

To call OpenAI's ChatGPT API from a C# application, you need to make HTTP requests using HttpClient. Here's an example of how to do this:

1. Set Up the Project:

   • Create a new C# Console Application in Visual Studio.
   • Install System.Net.Http and Newtonsoft.Json via NuGet Package Manager.

   Sample code 
   
   using System;
   using System.Net.Http;
   using System.Text;
   using System.Threading.Tasks;
   using Newtonsoft.Json;
   
   namespace ChatGPTExample
   {
       class Program
       {
           private static readonly string apiKey = "YOUR_API_KEY_HERE";
           private static readonly string endpoint = "https://api.openai.com/v1/completions";
   
           static async Task Main(string[] args)
           {
               string prompt = "Explain the significance of machine learning in modern technology.";
               var response = await GetChatGPTResponse(prompt);
               Console.WriteLine(response);
           }
   
           public static async Task<string> GetChatGPTResponse(string prompt)
           {
               using (var httpClient = new HttpClient())
               {
                   httpClient.DefaultRequestHeaders.Add("Authorization", $"Bearer {apiKey}");
   
                   var requestBody = new
                   {
                       model = "text-davinci-003",
                       prompt = prompt,
                       max_tokens = 150
                   };
   
                   var content = new StringContent(JsonConvert.SerializeObject(requestBody), Encoding.UTF8, "application/json");
                   var response = await httpClient.PostAsync(endpoint, content);
                   response.EnsureSuccessStatusCode();
   
                   var responseBody = await response.Content.ReadAsStringAsync();
                   dynamic result = JsonConvert.DeserializeObject(responseBody);
                   return result.choices[0].text;
               }
           }
       }
   }