VariantToStringWithDefault

// PROPSYS.dll
#include <windows.h>

LPWSTR VariantToStringWithDefault(
    const VARIANT* varIn,
    LPCWSTR pszDefault   // optional
);

<DllImport("PROPSYS.dll", ExactSpelling:=True)>
Public Shared Function VariantToStringWithDefault(
    varIn As IntPtr,   ' VARIANT*
    <MarshalAs(UnmanagedType.LPWStr)> pszDefault As String   ' LPCWSTR optional
) As IntPtr
End Function

' varIn : VARIANT*
' pszDefault : LPCWSTR optional
Declare PtrSafe Function VariantToStringWithDefault Lib "propsys" ( _
    ByVal varIn As LongPtr, _
    ByVal pszDefault As LongPtr) As LongPtr
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

VariantToStringWithDefault = ctypes.windll.propsys.VariantToStringWithDefault
VariantToStringWithDefault.restype = wintypes.LPWSTR
VariantToStringWithDefault.argtypes = [
    ctypes.c_void_p,  # varIn : VARIANT*
    wintypes.LPCWSTR,  # pszDefault : LPCWSTR optional
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('PROPSYS.dll')
VariantToStringWithDefault = Fiddle::Function.new(
  lib['VariantToStringWithDefault'],
  [
    Fiddle::TYPE_VOIDP,  # varIn : VARIANT*
    Fiddle::TYPE_VOIDP,  # pszDefault : LPCWSTR optional
  ],
  Fiddle::TYPE_VOIDP)

#[link(name = "propsys")]
extern "system" {
    fn VariantToStringWithDefault(
        varIn: *const VARIANT,  // VARIANT*
        pszDefault: *const u16  // LPCWSTR optional
    ) -> *mut u16;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("PROPSYS.dll")]
public static extern IntPtr VariantToStringWithDefault(IntPtr varIn, [MarshalAs(UnmanagedType.LPWStr)] string pszDefault);
"@
$api = Add-Type -MemberDefinition $sig -Name 'PROPSYS_VariantToStringWithDefault' -Namespace Win32 -PassThru
# $api::VariantToStringWithDefault(varIn, pszDefault)

#uselib "PROPSYS.dll"
#func global VariantToStringWithDefault "VariantToStringWithDefault" sptr, sptr
; VariantToStringWithDefault varptr(varIn), pszDefault   ; 戻り値は stat
; varIn : VARIANT* -> "sptr"
; pszDefault : LPCWSTR optional -> "sptr"
; ※HSP3.7は #func のため戻り値はシステム変数 stat に格納されます。

#uselib "PROPSYS.dll"
#cfunc global VariantToStringWithDefault "VariantToStringWithDefault" var, wstr
; res = VariantToStringWithDefault(varIn, pszDefault)
; varIn : VARIANT* -> "var"
; pszDefault : LPCWSTR optional -> "wstr"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

; LPWSTR VariantToStringWithDefault(VARIANT* varIn, LPCWSTR pszDefault)
#uselib "PROPSYS.dll"
#cfunc global VariantToStringWithDefault "VariantToStringWithDefault" var, wstr
; res = VariantToStringWithDefault(varIn, pszDefault)
; varIn : VARIANT* -> "var"
; pszDefault : LPCWSTR optional -> "wstr"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

import (
	"golang.org/x/sys/windows"
	"unsafe"
)

var (
	propsys = windows.NewLazySystemDLL("PROPSYS.dll")
	procVariantToStringWithDefault = propsys.NewProc("VariantToStringWithDefault")
)

// varIn (VARIANT*), pszDefault (LPCWSTR optional)
r1, _, err := procVariantToStringWithDefault.Call(
	uintptr(varIn),
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(pszDefault))),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // LPWSTR

function VariantToStringWithDefault(
  varIn: Pointer;   // VARIANT*
  pszDefault: PWideChar   // LPCWSTR optional
): PWideChar; stdcall;
  external 'PROPSYS.dll' name 'VariantToStringWithDefault';

result := DllCall("PROPSYS\VariantToStringWithDefault"
    , "Ptr", varIn   ; VARIANT*
    , "WStr", pszDefault   ; LPCWSTR optional
    , "Ptr")   ; return: LPWSTR

●VariantToStringWithDefault(varIn, pszDefault) = DLL("PROPSYS.dll", "char* VariantToStringWithDefault(void*, char*)")
# 呼び出し: VariantToStringWithDefault(varIn, pszDefault)
# varIn : VARIANT* -> "void*"
# pszDefault : LPCWSTR optional -> "char*"
# なでしこ1は32bit・ANSI(Shift_JIS)。文字列=char*(ANSI)、ポインタ/ハンドル=void*(4byte)。