Dotnet AI Examples

Welcome to Dotnet AI Examples – a collection of simple, focused sample projects that demonstrate how to work with LLMs (Large Language Models) using .NET.
These examples help .NET developers get hands-on experience with conversation loops, tool calling, document ingestion, and vector search using libraries like OpenAI, Azure OpenAI, Microsoft Semantic Kernel, Microsoft.Extensions.AI, and Pgvector.

Whether you're calling .NET methods with natural language, asking questions over ingested files, or doing similarity search over embeddings – this repo has a starting point for you.

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📦 Sample Projects

Sample	Description	Tech Used
OpenAITest	Illustrates how to interact with OpenAI in a conversational loop.	OpenAI.Chat
AzureOpenAITest	Illustrates how to interact with Azure OpenAI in a conversational loop.	OpenAI.Chat Azure.AI.OpenAI
IntroToMicrosoftExtensionsAI	Demonstrates how to use AIFunctionFactory to enable tool calling, allowing natural language input to trigger the C# method.	Microsoft.Extensions.AI
IntroToSemanticKernel	Shows tool calling using KernelFunction and KernelPlugin to expose C# methods as AI-invokable functions.	Microsoft.SemanticKernel
VectorSearchUsingPostgres	Illustrates how to generate embeddings with OpenAI and perform semantic search against a Postgres database using pgvector for vector similarity.	Pgvector

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⚙️ Setup

1. Clone the repo:

   git clone https://github.com/AvironSoftware/dotnet-ai-examples.git
   cd dotnet-ai-examples

2. Set your OpenAI API key:

   • Option 1:
     Instead of loading the key from an environment variable like this:

     Environment.GetEnvironmentVariable("OPENAI_API_KEY")

     You can hardcode your key directly for quick testing:

     "{your_openai_api_key}"

     Just replace {your_openai_api_key} with your actual OpenAI key (in quotes).
     Note: Avoid committing this version to source control for security reasons.

   • Option 2:
     Set it as an environment variable:

     export OPENAI_API_KEY=your-key-here

   • On Windows (PowerShell):

     $env:OPENAI_API_KEY="your-key-here"

3. Run Docker Desktop

   • IntroToSemanticKernel and VectorSearchUsingPostgres relies on Docker Desktop to be running for PostgressContainerFactory to initialize.

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🔑 How to Get an OpenAI API Key

1. Go to https://platform.openai.com/account/api-keys
2. Sign in or create an OpenAI account.
3. Click "Create new secret key".
4. Copy the key and keep it somewhere safe — you won’t be able to see it again!

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Enjoy exploring AI in .NET!