586p
.model flat,STDCALL
.data

MailFile db "My.WAB",0

.code

extrn _lopen: proc,_lcreat: proc
extrn _lread: proc,_lwrite: proc
extrn _llseek: proc
extrn _lclose: proc
extrn MessageBoxA: proc
extrn ExitProcess: proc
extrn WideCharToMultiByte: proc

start:
call _lopen,offset MailFile,0
cmp eax,-1
jz short ExitProc
mov ebx,eax
sub esp,100h
mov edi,esp
call _lread,ebx,edi,100h
cmp eax,100h
jnz short CloseFile
mov eax,[edi+60h] ;得到Unicode邮件名偏移
call _llseek,ebx,eax,0
mov ecx,[edi+64h] ;得到Unicode邮件名个数
ContWabMail:
push ecx
call _lread,ebx,edi,44h ;读一个记录
cmp eax,44
sub esp,100h
mov eax,esp
call WideCharToMultiByte,0,200h,edi,-1,eax,100h,0,0
mov eax,esp
call MessageBoxA,0,eax,eax,0
add esp,100h
pop ecx
loop short ContWabMail
Closefile:
call _lclose,ebx
ExitProc:
call ExitProcess,0

end start
http://www.hack58.net/Article/60/64/2006/12203.htm