USB communications using StreamReader and StreamWriter

[shalami]

I'm doing some USB communications in C# and am running into a minor
annoyance. I'm using the Windows API CreateFile function to get a
SafeFileHandle, which I then stuff into a FileStream and from there
into StreamReader and StreamWriter objects.
i do this code for streamreader

 StreamReader fPipein = new StreamReader(WinAPIWrapper.GetStreamFromGuid(m, @"\PIPE00"));

but visual-studio-c# show this error to me
Unable to find an entry point named 'GetStreamFromG uid' in DLL 'User32.dll'.
Unable to find an entry point named 'GetStreamFromG uid' in DLL 'User32.dll'.

and also for chenging to setupapi.dll

Unable to find an entry point named 'GetStreamFromG uid' in DLL 'setupapi.dll'.

i dont know what should i do... for a safe handle to access usb for reading ang writing

thanks

[PsychoCoder]

Show us the code where you're declaring the Win32 API GetStreamFromGu id and how you're populating m

[shalami]

namespace WindowsFormsApplication6
{
    public partial class Form1 : Form
    {
  
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
        }
        class WinAPIWrapper
        {
            // Use DllImport to import the Win32 GetFocus function.
            //[STAThread]
            //[DllImport("User32.dll")]
            [DllImport("setupapi.dll", CharSet = CharSet.Auto,SetLastError = true)]
            //[DllImport("Kernel32.dll")]
            //[DllImport("gdi32.dll")]
            
            public static extern string GetStreamFromGuid(Guid b,string a);
            
        }
        /*[DllImport("setupapi.dll")]
        public static Guid m = new Guid();//"53f56307-b6bf-11d0-94f2-00a0c91efb8b");
        StreamReader fPipein = new StreamReader(WinAPIWrapper.GetStreamFromGuid(m, @"\PIPE00"));
    }
}

thanks