.386
.model flat,stdcall
option casemap:none

include windows.inc
include user32.inc
includelib user32.lib
include kernel32.inc
includelib kernel32.lib

_ProcThread proto lParam:DWORD

.code

        ;DLL的入口函数.
        DllMain proc _hInstance,_dwReason,_dwReserved
        .if _dwReason==DLL_PROCESS_ATTACH
                invoke CreateThread,NULL,0,addr _ProcThread ,NULL,0,0
                invoke SetThreadPriority,eax,1
        .endif
        DllMain endp

        _ProcThread proc lParam:DWORD
        .while TRUE
                invoke Sleep,5000
                invoke MessageBox,0,0,0,1
        .endw
        ret
        _ProcThread endp

end DllMain

简单的DLL程序

新建工程的时候就有一个DLL PROJECT