OpenThemeData

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

HTHEME OpenThemeData(
    HWND hwnd,   // optional
    LPCWSTR pszClassList
);

<DllImport("UXTHEME.dll", ExactSpelling:=True)>
Public Shared Function OpenThemeData(
    hwnd As IntPtr,   ' HWND optional
    <MarshalAs(UnmanagedType.LPWStr)> pszClassList As String   ' LPCWSTR
) As IntPtr
End Function

' hwnd : HWND optional
' pszClassList : LPCWSTR
Declare PtrSafe Function OpenThemeData Lib "uxtheme" ( _
    ByVal hwnd As LongPtr, _
    ByVal pszClassList 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

OpenThemeData = ctypes.windll.uxtheme.OpenThemeData
OpenThemeData.restype = ctypes.c_ssize_t
OpenThemeData.argtypes = [
    wintypes.HANDLE,  # hwnd : HWND optional
    wintypes.LPCWSTR,  # pszClassList : LPCWSTR
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('UXTHEME.dll')
OpenThemeData = Fiddle::Function.new(
  lib['OpenThemeData'],
  [
    Fiddle::TYPE_VOIDP,  # hwnd : HWND optional
    Fiddle::TYPE_VOIDP,  # pszClassList : LPCWSTR
  ],
  Fiddle::TYPE_INTPTR_T)

#[link(name = "uxtheme")]
extern "system" {
    fn OpenThemeData(
        hwnd: *mut core::ffi::c_void,  // HWND optional
        pszClassList: *const u16  // LPCWSTR
    ) -> isize;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("UXTHEME.dll")]
public static extern IntPtr OpenThemeData(IntPtr hwnd, [MarshalAs(UnmanagedType.LPWStr)] string pszClassList);
"@
$api = Add-Type -MemberDefinition $sig -Name 'UXTHEME_OpenThemeData' -Namespace Win32 -PassThru
# $api::OpenThemeData(hwnd, pszClassList)

#uselib "UXTHEME.dll"
#func global OpenThemeData "OpenThemeData" sptr, sptr
; OpenThemeData hwnd, pszClassList   ; 戻り値は stat
; hwnd : HWND optional -> "sptr"
; pszClassList : LPCWSTR -> "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 "UXTHEME.dll"
#cfunc global OpenThemeData "OpenThemeData" sptr, wstr
; res = OpenThemeData(hwnd, pszClassList)
; hwnd : HWND optional -> "sptr"
; pszClassList : LPCWSTR -> "wstr"

; HTHEME OpenThemeData(HWND hwnd, LPCWSTR pszClassList)
#uselib "UXTHEME.dll"
#cfunc global OpenThemeData "OpenThemeData" intptr, wstr
; res = OpenThemeData(hwnd, pszClassList)
; hwnd : HWND optional -> "intptr"
; pszClassList : LPCWSTR -> "wstr"

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

var (
	uxtheme = windows.NewLazySystemDLL("UXTHEME.dll")
	procOpenThemeData = uxtheme.NewProc("OpenThemeData")
)

// hwnd (HWND optional), pszClassList (LPCWSTR)
r1, _, err := procOpenThemeData.Call(
	uintptr(hwnd),
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(pszClassList))),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HTHEME

function OpenThemeData(
  hwnd: THandle;   // HWND optional
  pszClassList: PWideChar   // LPCWSTR
): NativeInt; stdcall;
  external 'UXTHEME.dll' name 'OpenThemeData';

result := DllCall("UXTHEME\OpenThemeData"
    , "Ptr", hwnd   ; HWND optional
    , "WStr", pszClassList   ; LPCWSTR
    , "Ptr")   ; return: HTHEME

●OpenThemeData(hwnd, pszClassList) = DLL("UXTHEME.dll", "int OpenThemeData(void*, char*)")
# 呼び出し: OpenThemeData(hwnd, pszClassList)
# hwnd : HWND optional -> "void*"
# pszClassList : LPCWSTR -> "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)。