One may Get the SCARD_IO_REQUEST values which are defined as pointer to initialised data export in WinSCard.dll using the LoadLibrary and GetProcAddress pair.

If you use a struct rather than a class for SCARD_IO_REQUEST, don't forget to add "ref" to the pioRecvPci parameter in the signature. Alternatively, if you don't care about the returned protocol control information, change the pioRecvPci parameter to an "IntPtr" and pass "IntPtr.Zero" in as this parameter

UnsafeNativeMethods.SCARD_IO_REQUEST request = new UnsafeNativeMethods.SCARD_IO_REQUEST();

request.cbPciLength = System.Runtime.InteropServices.Marshal.SizeOf(typeof(UnsafeNativeMethods.SCARD_IO_REQUEST));

SCARD_IO_REQUEST ioRecv = new SCARD_IO_REQUEST();

Structures

2: SCARD_IO_REQUEST

Summary

The SCARD_IO_REQUEST structure begins a protocol control information structure. Any protocol-specific information then immediately follows this structure. The entire length of the structure must be aligned with the underlying hardware architecture word size. For example, in Win32 the length of any PCI information must be a multiple of four bytes so that it aligns on a 32-bit boundary.

struct SCARD_IO_REQUEST {

Documentation

[SCARD_IO_REQUEST] on MSDN

Access PInvoke.net directly from VS: