title: How can I configure OmniSharp to support intellisense for C# without the use of .NET Core or MSBuild configuration files?
body: <p>I am referencing Gtk# and building using Mono, writing my code in VS Code (code.visualstudio.com). I'd like intellisense for C#. By "intellisense" I mean the correct functions, members, etc. come up with "." - this is separate from predictive suggestions based on other code in the file.</p>
  
  <p>I have tried both the current Microsoft C# extension (<a href="https://marketplace.visualstudio.com/items?itemName=ms-vscode.csharp" rel="nofollow">https://marketplace.visualstudio.com/items?itemName=ms-vscode.csharp</a>) as well as the Legacy Microsoft C# extension (<a href="https://marketplace.visualstudio.com/items?itemName=ms-vscode.omnisharp" rel="nofollow">https://marketplace.visualstudio.com/items?itemName=ms-vscode.omnisharp</a>).</p>
  
  <p>Both of these appear to use OmniSharp as the means for providing intellisense, and both either load MS Build files and/or "project.json" files.</p>
  
  <p>The current Microsoft C# extension seems to use "project.json" files which appear to follow a schema specifically for .NET Core. I tried to leverage this anyway by creating a local GtkSharp NuGet package out of the Mono DLLs, but I could not then "dotnet restore" because these NuGet packages were incompatible with .NET Core. I followed: <a href="https://docs.nuget.org/ndocs/hosting-packages/local-feeds" rel="nofollow">https://docs.nuget.org/ndocs/hosting-packages/local-feeds</a> and <a href="https://docs.nuget.org/ndocs/create-packages/creating-a-package" rel="nofollow">https://docs.nuget.org/ndocs/create-packages/creating-a-package</a></p>
  
  <p>The Legacy Microsoft C# extension works if I use Visual Studio to generate solution (.sln) and project (.csproj) files. VS Code then recognizes these files and uses intellisense properly. Trying to hand-roll solution and project files failed because there seem to be a lot of entries OmniSharp is looking for when setting up using this method.</p>
  
  <p>Fundamentally, I want to provide a simple lightweight configuration which says: "Here is my code (.cs files), and here are the assemblies I reference (.dlls) as well as their comment files (.xml)" - and then have VS Code provide intellisense for those files and referenced assemblies. The .NET Core "project.json" files are simple enough, but are incompatible. The MS Build files are significantly more complicated than what I am looking for and require Visual Studio (or maybe a much deeper knowledge of MS Build) to generate OmniSharp compatible files. I'm looking for a separation between build configuration and intellisense configuration.</p>
  
  <p>How can I configure VS code to support intellisense for C# without the use of .NET Core or MSBuild?</p>
  
  <p><strong>This has nothing to do with build systems, and strictly relates to providing intellisense support using one of the OmniSharp-based C# VS Code extensions provided by Microsoft without the use of "project.json" or MS Build configuration files.</strong></p>