VarDateFromStr

// OLEAUT32.dll
#include <windows.h>

HRESULT VarDateFromStr(
    LPCWSTR strIn,
    DWORD lcid,
    DWORD dwFlags,
    DOUBLE* pdateOut
);

<DllImport("OLEAUT32.dll", ExactSpelling:=True)>
Public Shared Function VarDateFromStr(
    <MarshalAs(UnmanagedType.LPWStr)> strIn As String,   ' LPCWSTR
    lcid As UInteger,   ' DWORD
    dwFlags As UInteger,   ' DWORD
    <Out> ByRef pdateOut As Double   ' DOUBLE* out
) As Integer
End Function

' strIn : LPCWSTR
' lcid : DWORD
' dwFlags : DWORD
' pdateOut : DOUBLE* out
Declare PtrSafe Function VarDateFromStr Lib "oleaut32" ( _
    ByVal strIn As LongPtr, _
    ByVal lcid As Long, _
    ByVal dwFlags As Long, _
    ByRef pdateOut 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

VarDateFromStr = ctypes.windll.oleaut32.VarDateFromStr
VarDateFromStr.restype = ctypes.c_int
VarDateFromStr.argtypes = [
    wintypes.LPCWSTR,  # strIn : LPCWSTR
    wintypes.DWORD,  # lcid : DWORD
    wintypes.DWORD,  # dwFlags : DWORD
    ctypes.POINTER(ctypes.c_double),  # pdateOut : DOUBLE* out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('OLEAUT32.dll')
VarDateFromStr = Fiddle::Function.new(
  lib['VarDateFromStr'],
  [
    Fiddle::TYPE_VOIDP,  # strIn : LPCWSTR
    -Fiddle::TYPE_INT,  # lcid : DWORD
    -Fiddle::TYPE_INT,  # dwFlags : DWORD
    Fiddle::TYPE_VOIDP,  # pdateOut : DOUBLE* out
  ],
  Fiddle::TYPE_INT)

#[link(name = "oleaut32")]
extern "system" {
    fn VarDateFromStr(
        strIn: *const u16,  // LPCWSTR
        lcid: u32,  // DWORD
        dwFlags: u32,  // DWORD
        pdateOut: *mut f64  // DOUBLE* out
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("OLEAUT32.dll")]
public static extern int VarDateFromStr([MarshalAs(UnmanagedType.LPWStr)] string strIn, uint lcid, uint dwFlags, out double pdateOut);
"@
$api = Add-Type -MemberDefinition $sig -Name 'OLEAUT32_VarDateFromStr' -Namespace Win32 -PassThru
# $api::VarDateFromStr(strIn, lcid, dwFlags, pdateOut)

#uselib "OLEAUT32.dll"
#func global VarDateFromStr "VarDateFromStr" sptr, sptr, sptr, sptr
; VarDateFromStr strIn, lcid, dwFlags, varptr(pdateOut)   ; 戻り値は stat
; strIn : LPCWSTR -> "sptr"
; lcid : DWORD -> "sptr"
; dwFlags : DWORD -> "sptr"
; pdateOut : 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 "OLEAUT32.dll"
#cfunc global VarDateFromStr "VarDateFromStr" wstr, int, int, var
; res = VarDateFromStr(strIn, lcid, dwFlags, pdateOut)
; strIn : LPCWSTR -> "wstr"
; lcid : DWORD -> "int"
; dwFlags : DWORD -> "int"
; pdateOut : 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 VarDateFromStr(LPCWSTR strIn, DWORD lcid, DWORD dwFlags, DOUBLE* pdateOut)
#uselib "OLEAUT32.dll"
#cfunc global VarDateFromStr "VarDateFromStr" wstr, int, int, var
; res = VarDateFromStr(strIn, lcid, dwFlags, pdateOut)
; strIn : LPCWSTR -> "wstr"
; lcid : DWORD -> "int"
; dwFlags : DWORD -> "int"
; pdateOut : 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 (
	oleaut32 = windows.NewLazySystemDLL("OLEAUT32.dll")
	procVarDateFromStr = oleaut32.NewProc("VarDateFromStr")
)

// strIn (LPCWSTR), lcid (DWORD), dwFlags (DWORD), pdateOut (DOUBLE* out)
r1, _, err := procVarDateFromStr.Call(
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(strIn))),
	uintptr(lcid),
	uintptr(dwFlags),
	uintptr(pdateOut),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HRESULT

function VarDateFromStr(
  strIn: PWideChar;   // LPCWSTR
  lcid: DWORD;   // DWORD
  dwFlags: DWORD;   // DWORD
  pdateOut: Pointer   // DOUBLE* out
): Integer; stdcall;
  external 'OLEAUT32.dll' name 'VarDateFromStr';

result := DllCall("OLEAUT32\VarDateFromStr"
    , "WStr", strIn   ; LPCWSTR
    , "UInt", lcid   ; DWORD
    , "UInt", dwFlags   ; DWORD
    , "Ptr", pdateOut   ; DOUBLE* out
    , "Int")   ; return: HRESULT

●VarDateFromStr(strIn, lcid, dwFlags, pdateOut) = DLL("OLEAUT32.dll", "int VarDateFromStr(char*, dword, dword, void*)")
# 呼び出し: VarDateFromStr(strIn, lcid, dwFlags, pdateOut)
# strIn : LPCWSTR -> "char*"
# lcid : DWORD -> "dword"
# dwFlags : DWORD -> "dword"
# pdateOut : 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)。