excel - VBA call same C++ dll return different results -

i have test dll function reads string , display it:

int _stdcall test(lpstr mystring) { messageboxa(null, (lpcstr)mystring, "test", mb_ok); return 0;}

the excel vba declaration is

declare function test lib "test.dll" (byval text string) long

there sub calls function. reads excel cell value "abcde" , able display correct result. sub code is:

sub testcode()     test (cells(1,1).value) end sub

however when call dll function using excel formula =test(a1), message box display first char "a" of string.

i had spent entire weekend reading bstr, etc, still not able solve this. going on here?

declare imported function private:

private declare function test_internal lib "test.dll" alias "test" (byval text string) long

and create wrapper function excel use:

public function test (byval text string) long   test = test_internal(text) end functin

because apparently, while vb(a) converts string arguments ascii using current system codepage when calling declared apis, excel engine not.

on side note, might want remove parentheses.

And