Given the files vertex.vert and fragment.frag you can compile them by simply using:
var compiler = new Compiler();
var vert = File.ReadAllText("vertex.vert");
var frag = File.ReadAllText("fragment.frag");
var vertres = compiler.Compile(vert, CompileType.CodeToSPIRV, ShaderKind.VertexShader);
var fragres = compiler.Compile(frag, CompileType.CodeToSPIRV, ShaderKind.FragmentShader);
To display Errors you can just:
if (vertres.Status != CompilationStatus.Success)
Console.WriteLine(vertres.ErrorMessage);
if (fragres.Status != CompilationStatus.Success)
Console.WriteLine(fragres.ErrorMessage);
To write the result to a file just:
if (vertres.Code is not null) File.WriteAllBytes("vertex.spv", vertres.Code);
if (fragres.Code is not null) File.WriteAllBytes("fragment.spv", fragres.Code);
There's a NuGet package right here