NMHEADERW

using System;
using System.Runtime.InteropServices;

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct NMHDR
{
    public IntPtr hwndFrom;
    public UIntPtr idFrom;
    public uint code;
}

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct NMHEADERW
{
    public NMHDR hdr;
    public int iItem;
    public int iButton;
    public IntPtr pitem;
}

Imports System.Runtime.InteropServices

<StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Unicode)>
Public Structure NMHDR
    Public hwndFrom As IntPtr
    Public idFrom As UIntPtr
    Public code As UInteger
End Structure

<StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Unicode)>
Public Structure NMHEADERW
    Public hdr As NMHDR
    Public iItem As Integer
    Public iButton As Integer
    Public pitem As IntPtr
End Structure

import ctypes
from ctypes import wintypes

class NMHDR(ctypes.Structure):
    _fields_ = [
        ("hwndFrom", ctypes.c_void_p),
        ("idFrom", ctypes.c_size_t),
        ("code", wintypes.DWORD),
    ]

class NMHEADERW(ctypes.Structure):
    _fields_ = [
        ("hdr", NMHDR),
        ("iItem", ctypes.c_int),
        ("iButton", ctypes.c_int),
        ("pitem", ctypes.c_void_p),
    ]

#[repr(C)]
pub struct NMHDR {
    pub hwndFrom: *mut core::ffi::c_void,
    pub idFrom: usize,
    pub code: u32,
}

#[repr(C)]
pub struct NMHEADERW {
    pub hdr: NMHDR,
    pub iItem: i32,
    pub iButton: i32,
    pub pitem: *mut core::ffi::c_void,
}

import "golang.org/x/sys/windows"

type NMHDR struct {
	hwndFrom uintptr
	idFrom uintptr
	code uint32
}

type NMHEADERW struct {
	hdr NMHDR
	iItem int32
	iButton int32
	pitem uintptr
}

type
  NMHDR = record
    hwndFrom: Pointer;
    idFrom: NativeUInt;
    code: DWORD;
  end;

  NMHEADERW = record
    hdr: NMHDR;
    iItem: Integer;
    iButton: Integer;
    pitem: Pointer;
  end;

const NMHDR = extern struct {
    hwndFrom: ?*anyopaque,
    idFrom: usize,
    code: u32,
};

const NMHEADERW = extern struct {
    hdr: NMHDR,
    iItem: i32,
    iButton: i32,
    pitem: ?*anyopaque,
};

type
  NMHDR {.bycopy.} = object
    hwndFrom: pointer
    idFrom: uint
    code: uint32

  NMHEADERW {.bycopy.} = object
    hdr: NMHDR
    iItem: int32
    iButton: int32
    pitem: pointer

struct NMHDR
{
    void* hwndFrom;
    size_t idFrom;
    uint code;
}

struct NMHEADERW
{
    NMHDR hdr;
    int iItem;
    int iButton;
    void* pitem;
}