VariantGetDoubleElem

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

HRESULT VariantGetDoubleElem(
    const VARIANT* var,
    DWORD iElem,
    DOUBLE* pnVal
);

<DllImport("PROPSYS.dll", ExactSpelling:=True)>
Public Shared Function VariantGetDoubleElem(
    var As IntPtr,   ' VARIANT*
    iElem As UInteger,   ' DWORD
    <Out> ByRef pnVal As Double   ' DOUBLE* out
) As Integer
End Function

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

import ctypes
from ctypes import wintypes

VariantGetDoubleElem = ctypes.windll.propsys.VariantGetDoubleElem
VariantGetDoubleElem.restype = ctypes.c_int
VariantGetDoubleElem.argtypes = [
    ctypes.c_void_p,  # var : VARIANT*
    wintypes.DWORD,  # iElem : DWORD
    ctypes.POINTER(ctypes.c_double),  # pnVal : DOUBLE* out
]

require 'fiddle'
require 'fiddle/import'

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

#[link(name = "propsys")]
extern "system" {
    fn VariantGetDoubleElem(
        var: *const VARIANT,  // VARIANT*
        iElem: u32,  // DWORD
        pnVal: *mut f64  // DOUBLE* out
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

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

#uselib "PROPSYS.dll"
#func global VariantGetDoubleElem "VariantGetDoubleElem" sptr, sptr, sptr
; VariantGetDoubleElem varptr(var), iElem, varptr(pnVal)   ; 戻り値は stat
; var : VARIANT* -> "sptr"
; iElem : DWORD -> "sptr"
; pnVal : DOUBLE* 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 VariantGetDoubleElem "VariantGetDoubleElem" var, int, var
; res = VariantGetDoubleElem(var, iElem, pnVal)
; var : VARIANT* -> "var"
; iElem : DWORD -> "int"
; pnVal : DOUBLE* 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 VariantGetDoubleElem(VARIANT* var, DWORD iElem, DOUBLE* pnVal)
#uselib "PROPSYS.dll"
#cfunc global VariantGetDoubleElem "VariantGetDoubleElem" var, int, var
; res = VariantGetDoubleElem(var, iElem, pnVal)
; var : VARIANT* -> "var"
; iElem : DWORD -> "int"
; pnVal : DOUBLE* 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")
	procVariantGetDoubleElem = propsys.NewProc("VariantGetDoubleElem")
)

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

function VariantGetDoubleElem(
  var: Pointer;   // VARIANT*
  iElem: DWORD;   // DWORD
  pnVal: Pointer   // DOUBLE* out
): Integer; stdcall;
  external 'PROPSYS.dll' name 'VariantGetDoubleElem';

result := DllCall("PROPSYS\VariantGetDoubleElem"
    , "Ptr", var   ; VARIANT*
    , "UInt", iElem   ; DWORD
    , "Ptr", pnVal   ; DOUBLE* out
    , "Int")   ; return: HRESULT

●VariantGetDoubleElem(var, iElem, pnVal) = DLL("PROPSYS.dll", "int VariantGetDoubleElem(void*, dword, void*)")
# 呼び出し: VariantGetDoubleElem(var, iElem, pnVal)
# var : VARIANT* -> "void*"
# iElem : DWORD -> "dword"
# pnVal : DOUBLE* 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)。