csharp.md
In Uno: R Interface to the 'Uno' Nonlinear Optimization Solver

CSharp

Build from source

There is a C# example code in examples/call_highs_from_csharp.cs. From the HiGHS root directory, run

cmake -S. -Bbuild -DCSHARP=ON

If a CSharp compiler is available, this builds the example using CMake and generates a binary in the build directory (build/bin/csharpexample).

NuGet

The nuget package Highs.Native is on https://www.nuget.org, at https://www.nuget.org/packages/Highs.Native/.

It can be added to your C# project with dotnet

dotnet add package Highs.Native --version 1.14.0

The nuget package contains runtime libraries for

win-x64
win-x32
linux-x64
linux-arm64
macos-x64
macos-arm64

Details for building locally can be found in nuget/README.md. Many thanks to Markus-Ludwig Wermer and the team at MENTZ GmbH for the NuGet packaging support!

C# API

The C# API can be called directly. Here are observations on calling the HiGHS C# API from C#:

The file HiGHS/highs/interfaces/highs_csharp_api.cs contains all the PInvoke you need.
Make sure, that the native HiGHS library (highs.dll, libhighs.dll, libhighs.so, ... depending on your platform) can be found at runtime. How to do this is platform dependent, copying it next to your C# executable should work in most cases. You can use msbuild for that. On linux, installing HiGHS system wide should work.
Make sure that all dependencies of the HiGHS library can be found, too. For example, if HiGHS was build using Visual C++ make sure that the MSVCRuntime is installed on the machine you want to run your application on.
Depending on the name of your HiGHS library, it might be necessary to change the constant "highslibname". See document on writing cross platform P/Invoke code if necessary.
Call the Methods in highs_csharp_api.cs and have fun with HiGHS.