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Using Github Copilot in Visual Studio

With GitHub Copilot you get autocomplete-style suggestions from an AI pair programmer as you code. Let me show you how to get started with Github Copilot in Visual Studio.

Remark: Before you can start you need to have an active GitHub Copilot subscription.

Install the extension

You can install the extension directly in Visual Studio.

  • Therefore go to Extensions –> Manage Extensions in Visual Studio.
  • Search for Github Copilot and click on Download.

  • After restarting Visual Studio, Visual Studio will ask you to active Github Copilot on your device. After walking through the device activation flow, you are finally ready to go.

Writing code with Github Copilot

Now that our extensions is up and running, let us write some code. When using Github Copilot it feels like you have a lot smarter Intellisense available.

I create a Book class and when I try to add a property Visual Studio is aware that I want to add typical properties for a book, so I get suggestions like title, author, etc…

I can hit Tab to accept the suggestion or Alt+; to get another suggestion:

If I want to see a whole list of possible suggestions, I can click on the Github Copilot icon at the bottom of my editor and click on Open Copilot. Now a separate Copilot window is loaded were I get a range of of possible solutions:

I can use one of the provided solutions by clicking on Accept solution.

Of course we can do more. A second thing we can do is writing a meaningful method signature and Github Copilot will try to understand what it should do and provide us with a suggestion.

For example I wrote an IsValidISBN() method to validate if the provided ISBN number is indeed a valid one. I could look up what are the validation rules for an ISBN number but Github Copilot already provides me a possible implementation:

A similar thing is possible through code comments. Use natural language to write a comment about what you expect. This can be one or more lines.

For example I asked Github copilot to write me an XUnit test for my IsValidISBN() method:

This is certainly a useful help to become a more productive developer.

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