摘要:C# get a string from a C++ DLL
以前在 MSDN 上的討論串，搬到這裡做備忘。範例程式碼在此：gpDllNet.rar
C++ DLL ：
TCHAR g_awcMessage[] = L"Hello中文"; char g_aszMessage[] = "Hello中文"; extern "C" __declspec(dllexport) TCHAR* __stdcall GetHelloL() 
{ 
return g_awcMessage; 
} extern "C" __declspec(dllexport) CHAR* __stdcall GetHello() 
{ 
return g_aszMessage; } extern "C" __declspec(dllexport) int __stdcall GetInt() { return 100; 
}C# P/Invoke：
[DllImport("gpDll.dll")] public static extern IntPtr GetHello(); [DllImport("gpDll.dll")] public static extern IntPtr GetHelloL(); [DllImport("gpDll.dll")] public static extern int GetInt(); private void button1_Click(object sender, EventArgs e) { // Not support in CF //Marshal.PtrToStringAnsi //Marshal.PtrToStringAuto // Multibytes 會變成亂碼 string str = Marshal.PtrToStringUni(GetHello()); // Wide Character 顯示正常 string strL = Marshal.PtrToStringUni(GetHelloL()); int n = GetInt(); }