GetDlgItem

// USER32.dll
#include <windows.h>

HWND GetDlgItem(
    HWND hDlg,   // optional
    INT nIDDlgItem
);

<DllImport("USER32.dll", SetLastError:=True, ExactSpelling:=True)>
Public Shared Function GetDlgItem(
    hDlg As IntPtr,   ' HWND optional
    nIDDlgItem As Integer   ' INT
) As IntPtr
End Function

' hDlg : HWND optional
' nIDDlgItem : INT
Declare PtrSafe Function GetDlgItem Lib "user32" ( _
    ByVal hDlg As LongPtr, _
    ByVal nIDDlgItem As Long) As LongPtr
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

GetDlgItem = ctypes.windll.user32.GetDlgItem
GetDlgItem.restype = ctypes.c_void_p
GetDlgItem.argtypes = [
    wintypes.HANDLE,  # hDlg : HWND optional
    ctypes.c_int,  # nIDDlgItem : INT
]
# GetLastError: use ctypes.GetLastError() (or ctypes.WinDLL(use_last_error=True))

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('USER32.dll')
GetDlgItem = Fiddle::Function.new(
  lib['GetDlgItem'],
  [
    Fiddle::TYPE_VOIDP,  # hDlg : HWND optional
    Fiddle::TYPE_INT,  # nIDDlgItem : INT
  ],
  Fiddle::TYPE_VOIDP)

#[link(name = "user32")]
extern "system" {
    fn GetDlgItem(
        hDlg: *mut core::ffi::c_void,  // HWND optional
        nIDDlgItem: i32  // INT
    ) -> *mut core::ffi::c_void;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("USER32.dll", SetLastError = true)]
public static extern IntPtr GetDlgItem(IntPtr hDlg, int nIDDlgItem);
"@
$api = Add-Type -MemberDefinition $sig -Name 'USER32_GetDlgItem' -Namespace Win32 -PassThru
# $api::GetDlgItem(hDlg, nIDDlgItem)

#uselib "USER32.dll"
#func global GetDlgItem "GetDlgItem" sptr, sptr
; GetDlgItem hDlg, nIDDlgItem   ; 戻り値は stat
; hDlg : HWND optional -> "sptr"
; nIDDlgItem : INT -> "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 "USER32.dll"
#cfunc global GetDlgItem "GetDlgItem" sptr, int
; res = GetDlgItem(hDlg, nIDDlgItem)
; hDlg : HWND optional -> "sptr"
; nIDDlgItem : INT -> "int"

; HWND GetDlgItem(HWND hDlg, INT nIDDlgItem)
#uselib "USER32.dll"
#cfunc global GetDlgItem "GetDlgItem" intptr, int
; res = GetDlgItem(hDlg, nIDDlgItem)
; hDlg : HWND optional -> "intptr"
; nIDDlgItem : INT -> "int"

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

var (
	user32 = windows.NewLazySystemDLL("USER32.dll")
	procGetDlgItem = user32.NewProc("GetDlgItem")
)

// hDlg (HWND optional), nIDDlgItem (INT)
r1, _, err := procGetDlgItem.Call(
	uintptr(hDlg),
	uintptr(nIDDlgItem),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HWND

function GetDlgItem(
  hDlg: THandle;   // HWND optional
  nIDDlgItem: Integer   // INT
): THandle; stdcall;
  external 'USER32.dll' name 'GetDlgItem';

result := DllCall("USER32\GetDlgItem"
    , "Ptr", hDlg   ; HWND optional
    , "Int", nIDDlgItem   ; INT
    , "Ptr")   ; return: HWND

●GetDlgItem(hDlg, nIDDlgItem) = DLL("USER32.dll", "void* GetDlgItem(void*, int)")
# 呼び出し: GetDlgItem(hDlg, nIDDlgItem)
# hDlg : HWND optional -> "void*"
# nIDDlgItem : INT -> "int"
# 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)。