The library allows you to work with native libraries. Standard approach with the DllImport
attribute may be inconvenient if you want to build AnyCPU assembly with MS.NET/Mono support. The InteropRuntimeImplementer
class can generate implementation of interface with target signatures of native methods.
For example, let's create a native library (NativeLib
) with the function int sum(int a, int b) { return a + b; }
and build it in four configuration (Windows/Unix, x86/x64):
x86/NativeLib.dll
x86/libNativeLib.so
x64/NativeLib.dll
x64/libNativeLib.so
Now we can write the following code:
public interface INative
{
[RuntimeDllImport("NativeLib", CallingConvention = CallingConvention.Cdecl, EntryPoint = "sum")]
int Sum(int a, int b);
}
class Program
{
static void Main()
{
var native = InteropRuntimeImplementer.CreateInstance<INative>();
Console.WriteLine("2 + 3 = " + native.Sum(2, 3));
}
}
In the program, we declared interface INative
with signatures of the target native methods. Each signature should be marked with the RuntimeDllImport
attribute with name of a native library and other options. The instance of InteropRuntimeImplementer
helped us to create instance of the INative
interface on the fly. The implementation of the sum
method call corresponding native method from library that correspond to current architecture and OS. The InteropRuntimeImplementer
generates the following code:
namespace InteropRuntimeImplementer.NativeInstance
{
[UnmanagedFunctionPointer(CallingConvention.Cdecl, BestFitMapping = false, CharSet = (CharSet) 0, SetLastError = false, ThrowOnUnmappableChar = false)]
[StructLayout(LayoutKind.Auto, CharSet = CharSet.Auto)]
public delegate int SumDelegate(int a, int b);
public class NativeImplementation : INative
{
private SumDelegate SumField;
public NativeImplementation(LibraryLoader loader)
{
IntPtr dllHandle = loader.LoadLibrary("NativeLib", (string) null);
this.SumField = (SumDelegate) Marshal.GetDelegateForFunctionPointer(loader.GetProcAddress(dllHandle, "sum"), typeof (SumDelegate));
}
public int Sum(int a, int b)
{
return this.SumField(a, b);
}
}
}
As a result, we received a single .NET cross-platform AnyCPU-program with calls of native methods because of the LibraryLoader
class loaded handles for specific user environment.
You can install the library via NuGet: https://www.nuget.org/packages/InteropDotNet/