c# - 在 C# 中使用 C++ 引用中的引用从 C# 错误调用 C++ 代码

Question

所以在我的 c++.dll 文件中我得到了以下函数:

    DLL void GetUserPass(char* &userName, char* &passWord)
{
    userName = "ceva";
    passWord = "altceva";
}

现在我想从 C# 中调用它，但它给了我一个错误:

[DllImport("myDLL.dll")]
private static extern void GetUserPass(ref string userName, ref string passWord);

static void f()
{
        string userName ="";
        string passWord ="";

        GetUserPass(ref userName, ref passWord);
}

错误是:

A call to PInvoke function 'Download FTP Archive!Download_FTP_Archive.Program::GetUserPass' has unbalanced the stack. This is likely because the managed PInvoke signature does not match the unmanaged target signature. Check that the calling convention and parameters of the PInvoke signature match the target unmanaged signature.

我是否应该在 C++ dll 文件中尝试类似这样的内容:

using std::string;
 DLL void GetUserPass(string &userName, string &passWord)
{
    userName = "ceva";
    passWord = "altceva";
}

Answer 1

尝试以下操作:

DLL void __stdcall GetUserPass(char* &userName, char* &passWord)
{
    userName = "ceva";
    passWord = "altceva";
}



[DllImport("myDLL.dll", CharSet = CharSet.Ansi, CallingConvention = CallingConvention.StdCall)]
private static extern void GetUserPass(ref IntPtr userName, ref IntPtr passWord);
static void f()
{
        IntPtr userNamePtr = new IntPtr();
        IntPtr passWordPtr = new IntPtr();
        GetUserPass(ref userNamePtr, ref passWordPtr);
        string userName = Marshal.PtrToStringAnsi( userNamePtr );
        string passWord = Marshal.PtrToStringAnsi( passWordPtr );
}