Question

I have a C++ Dll “TheFoo.dll” with a method “Foo()”

I have access to other C++ code that uses this method by simply calling:

Foo();

I believe the Method does have the:

 __declspec( dllexport )

So, with the reading I’ve done about P/Invoke, i thought i should be able to simply call the same method from my C# code:

namespace PInvokeExample1
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();

        }


        [DllImport(@"C:\MyFolder\TheFoo.dll")]
        public static extern
            void Foo();

        private void button1_Click(object sender, RoutedEventArgs e)
        {
            Foo();

        }



    }
}

When i run it, i get an error:

Unable to find an entry point named 'Foo' in DLL 'C:\MyFolder\TheFoo.dll'.

Any ideas why it is not found?

Answer 1

You should provide more information on your C++. Try using extern "C" __declspec(dllexport) instead. C++ exports with strange names so using extern "C" avoids that.