How can I access the members of a struct after I passed it to a function.

.hadditem equ ebp - 0x88
.additem.hinstance equ ebp - 0x84
.additem.height equ ebp - 0x80
.additem.style equ ebp - 0x7c
.additem.exstyle equ ebp - 0x78
.additem.title equ ebp - 0x74
.additem.class equ ebp - 0x70

lea eax,[ebp-0x84]
mov dword [.hadditem],eax

push dword [.hadditem]
push dword 0x00000100
push BM_ADDITEM ;WM_USER+1
push dword [.hwnd]
call [user32.SendMessageW]

;function with only access to additem struct address passed via lparam
;this only copies the address
;already tried [.lparam+20] with messageboxw but that doesn't work either
mov eax,[.lparam]
mov [.hadditem],eax

Found it!

push dword 0x00000018
push dword [.lparam]
push dword [.hadditem]
call [crt.memcpy]