VariantGetStringElem

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

HRESULT VariantGetStringElem(
    const VARIANT* var,
    DWORD iElem,
    LPWSTR* ppszVal
);

<DllImport("PROPSYS.dll", ExactSpelling:=True)>
Public Shared Function VariantGetStringElem(
    var As IntPtr,   ' VARIANT*
    iElem As UInteger,   ' DWORD
    ppszVal As IntPtr   ' LPWSTR* out
) As Integer
End Function

' var : VARIANT*
' iElem : DWORD
' ppszVal : LPWSTR* out
Declare PtrSafe Function VariantGetStringElem Lib "propsys" ( _
    ByVal var As LongPtr, _
    ByVal iElem As Long, _
    ByVal ppszVal As LongPtr) As Long
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

VariantGetStringElem = ctypes.windll.propsys.VariantGetStringElem
VariantGetStringElem.restype = ctypes.c_int
VariantGetStringElem.argtypes = [
    ctypes.c_void_p,  # var : VARIANT*
    wintypes.DWORD,  # iElem : DWORD
    ctypes.c_void_p,  # ppszVal : LPWSTR* out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('PROPSYS.dll')
VariantGetStringElem = Fiddle::Function.new(
  lib['VariantGetStringElem'],
  [
    Fiddle::TYPE_VOIDP,  # var : VARIANT*
    -Fiddle::TYPE_INT,  # iElem : DWORD
    Fiddle::TYPE_VOIDP,  # ppszVal : LPWSTR* out
  ],
  Fiddle::TYPE_INT)

#[link(name = "propsys")]
extern "system" {
    fn VariantGetStringElem(
        var: *const VARIANT,  // VARIANT*
        iElem: u32,  // DWORD
        ppszVal: *mut *mut u16  // LPWSTR* out
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("PROPSYS.dll")]
public static extern int VariantGetStringElem(IntPtr var, uint iElem, IntPtr ppszVal);
"@
$api = Add-Type -MemberDefinition $sig -Name 'PROPSYS_VariantGetStringElem' -Namespace Win32 -PassThru
# $api::VariantGetStringElem(var, iElem, ppszVal)

#uselib "PROPSYS.dll"
#func global VariantGetStringElem "VariantGetStringElem" sptr, sptr, sptr
; VariantGetStringElem varptr(var), iElem, varptr(ppszVal)   ; 戻り値は stat
; var : VARIANT* -> "sptr"
; iElem : DWORD -> "sptr"
; ppszVal : LPWSTR* out -> "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 VariantGetStringElem "VariantGetStringElem" var, int, var
; res = VariantGetStringElem(var, iElem, ppszVal)
; var : VARIANT* -> "var"
; iElem : DWORD -> "int"
; ppszVal : LPWSTR* out -> "var"
; ※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。

; HRESULT VariantGetStringElem(VARIANT* var, DWORD iElem, LPWSTR* ppszVal)
#uselib "PROPSYS.dll"
#cfunc global VariantGetStringElem "VariantGetStringElem" var, int, var
; res = VariantGetStringElem(var, iElem, ppszVal)
; var : VARIANT* -> "var"
; iElem : DWORD -> "int"
; ppszVal : LPWSTR* out -> "var"
; ※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")
	procVariantGetStringElem = propsys.NewProc("VariantGetStringElem")
)

// var (VARIANT*), iElem (DWORD), ppszVal (LPWSTR* out)
r1, _, err := procVariantGetStringElem.Call(
	uintptr(var),
	uintptr(iElem),
	uintptr(ppszVal),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HRESULT

function VariantGetStringElem(
  var: Pointer;   // VARIANT*
  iElem: DWORD;   // DWORD
  ppszVal: PPWideChar   // LPWSTR* out
): Integer; stdcall;
  external 'PROPSYS.dll' name 'VariantGetStringElem';

result := DllCall("PROPSYS\VariantGetStringElem"
    , "Ptr", var   ; VARIANT*
    , "UInt", iElem   ; DWORD
    , "Ptr", ppszVal   ; LPWSTR* out
    , "Int")   ; return: HRESULT

●VariantGetStringElem(var, iElem, ppszVal) = DLL("PROPSYS.dll", "int VariantGetStringElem(void*, dword, void*)")
# 呼び出し: VariantGetStringElem(var, iElem, ppszVal)
# var : VARIANT* -> "void*"
# iElem : DWORD -> "dword"
# ppszVal : LPWSTR* out -> "void*"
# 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)。