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c#dllinteropsilverlight-5.0

How to load a dll with its dependencies with LoadLibrary or any other method


I'm trying to load a library, to use with interop, that has some dll dependencies, all names are known to me, but the location is dynamic. I can call LoadLibrary on the "main" dll, and it works fine if the others are on the working directory, which isn't the case. I tried calling LoadLibrary on everybody but its useless.

Any ideas? Is there an alternative to LoadLibrary?

.NET 4.5 siverlight5 project, interop with fortran.

        var interopPath = CreateDllFromResource(dllName);
        var d1=CreateDllFromResource("libgcc_s_dw2-1.dll");
        var d2 = CreateDllFromResource("libgfortran-3.dll");
        var d3 = CreateDllFromResource("libquadmath-0.dll");


        pDll = NativeMethods.LoadLibrary(interopPath);
        NativeMethods.LoadLibrary(d1);
        NativeMethods.LoadLibrary(d2);
        NativeMethods.LoadLibrary(d3);
        //oh dear, error handling here
        if (pDll == IntPtr.Zero)
        {
            throw new Exception("Dll Pointer is null! // Path: " + interopPath + "// Error: " + WSAGetLastError());
        }

        IntPtr pAddressOfFunctionToCall = NativeMethods.GetProcAddress(pDll, "ingammaextern_");
        if (pAddressOfFunctionToCall == IntPtr.Zero)
        {
            throw new Exception("Function Pointer is null!");
        }

Solution

  • Had to call LoadLibrary and use SetDllDirectory for it to work, using DllImport instead of LoadLibrary does not work.

        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            private delegate void ingammaextern_(StringBuilder resulfilesparam);
    
    
    
    {
       var dllName = "SubsCalculator1.dll";
    
                var interopPath = CreateDllFromResource(dllName);
                var d1 = CreateDllFromResource("libgcc_s_dw2-1.dll");
                var d2 = CreateDllFromResource("libgfortran-3.dll");
                var d3 = CreateDllFromResource("libquadmath-0.dll");
    
                string folderPath ="C:\folder\
                SetDllDirectory(folderPath);
    
                pDll = NativeMethods.LoadLibrary(interopPath);
    }