MUI: esempio di impostazioni Application-Specific (pre-Windows Vista)
L'applicazione di esempio descritta in questo argomento è simile a quella illustrata in MUI: Application-Specific Settings Sample (Windows Vista), ad eccezione del fatto che questa applicazione verrà eseguita in Windows 2000 e versioni successive. La differenza principale rispetto all'altro esempio è che il fallback del linguaggio deve essere personalizzato per l'esecuzione in più sistemi operativi.
Questa applicazione analizza prima un elenco di lingue delimitate in un file di testo e lo converte in un elenco di lingue a più stringhe per definire le preferenze di lingua specifiche dell'applicazione. I delimitatori supportati nell'esempio sono ",", ";", ":" e " ". Dopo l'analisi dell'elenco, il codice trova e carica le risorse nella lingua identificata. A differenza degli altri esempi di impostazioni specifiche dell'applicazione, questo codice carica e rilascia i file di risorse usando le chiamate alle funzioni MUI LoadMUILibrary e FreeMUILibrary.
// Down-Level enabled application that will work with Windows 2000 and later
#include <windows.h>
#include <wchar.h>
#include <strsafe.h>
#include <Nlsdl.h>
#include <MUILoad.h>
#include "resource.h"
#define SUFFICIENTLY_LARGE_STRING_BUFFER (MAX_PATH*2)
#define USER_CONFIGURATION_STRING_BUFFER (((LOCALE_NAME_MAX_LENGTH+1)*5)+1)
#define SUFFICIENTLY_LARGE_ERROR_BUFFER (1024*2)
BOOL GetMyUserDefinedLanguages(WCHAR * langStr, DWORD langStrSize);
BOOL ConvertMyLangStrToMultiLangStr(WCHAR * langStr, WCHAR * langMultiStr, DWORD langMultiStrSize);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
UNREFERENCED_PARAMETER(hInstance);
UNREFERENCED_PARAMETER(hPrevInstance);
UNREFERENCED_PARAMETER(lpCmdLine);
UNREFERENCED_PARAMETER(nCmdShow);
// The following code presents a hypothetical, yet common use pattern of MUI technology
WCHAR displayBuffer[SUFFICIENTLY_LARGE_ERROR_BUFFER];
// 1. Application starts by applying any user defined language preferences
// (language setting is potentially optional for an application that wishes to strictly use OS system language fallback)
// 1a. Application looks in pre-defined location for user preferences (registry, file, web, etc.)
WCHAR userLanguagesString[USER_CONFIGURATION_STRING_BUFFER*2];
if(!GetMyUserDefinedLanguages(userLanguagesString,USER_CONFIGURATION_STRING_BUFFER*2))
{
swprintf_s(displayBuffer,SUFFICIENTLY_LARGE_ERROR_BUFFER,L"FAILURE: Unable to find the user defined language configuration, last error = %d.",GetLastError());
MessageBoxW(NULL,displayBuffer,L"HelloMUI ERROR!",MB_OK | MB_ICONERROR);
return 1; // exit
}
// 1b. Application converts the user defined 'readable' languages to the proper multi-string 'less readable' language name format
WCHAR userLanguagesMultiString[USER_CONFIGURATION_STRING_BUFFER];
if(!ConvertMyLangStrToMultiLangStr(userLanguagesString,userLanguagesMultiString,USER_CONFIGURATION_STRING_BUFFER))
{
swprintf_s(displayBuffer,SUFFICIENTLY_LARGE_ERROR_BUFFER,L"FAILURE: Unable to convert the user defined language configuration to multi-string, last error = %d.",GetLastError());
MessageBoxW(NULL,displayBuffer,L"HelloMUI ERROR!",MB_OK | MB_ICONERROR);
return 1; // exit
}
// 1c. Application now attempts to set the fallback list - this is much different for a down-level
// shipping application when compared to a Vista or Windows 7 only shipping application
BOOL setSuccess = FALSE;
DWORD setLangCount = 0;
HMODULE hDLL = GetModuleHandleW(L"kernel32.dll");
if( hDLL )
{
typedef BOOL (* SET_PREFERRED_UI_LANGUAGES_PROTOTYPE ) ( DWORD, PCWSTR, PULONG );
SET_PREFERRED_UI_LANGUAGES_PROTOTYPE fp_SetPreferredUILanguages = (SET_PREFERRED_UI_LANGUAGES_PROTOTYPE)NULL;
fp_SetPreferredUILanguages = (SET_PREFERRED_UI_LANGUAGES_PROTOTYPE) GetProcAddress(hDLL,"SetProcessPreferredUILanguages");
if( fp_SetPreferredUILanguages )
{
// call SetProcessPreferredUILanguages if it is available in Kernel32.dll's export table - Windows 7 and later
setSuccess = fp_SetPreferredUILanguages(MUI_LANGUAGE_NAME,userLanguagesMultiString,&setLangCount);
}
else
{
fp_SetPreferredUILanguages = (SET_PREFERRED_UI_LANGUAGES_PROTOTYPE) GetProcAddress(hDLL,"SetThreadPreferredUILanguages");
// call SetThreadPreferredUILanguages if it is available in Kernel32.dll's export table - Windows Vista and later
if(fp_SetPreferredUILanguages)
setSuccess = fp_SetPreferredUILanguages(MUI_LANGUAGE_NAME,userLanguagesMultiString,&setLangCount);
}
}
// 2. Application obtains access to the proper resource container
// for standard Win32 resource loading this is normally a PE module
// LoadMUILibrary is the preferred alternative for loading of resource modules
// when the application is potentially run on OS versions prior to Vista
// LoadMUILibrary is available via Windows SDK releases in Vista and later
// When available, it is advised to get the most up-to-date Windows SDK (e.g., Windows 7)
HMODULE resContainer = NULL;
if(setSuccess) // Vista and later OS scenario
{
resContainer = LoadMUILibraryW(HELLO_MODULE_CONTRIVED_FILE_PATH,MUI_LANGUAGE_NAME,0);
}
else // this block should only be hit on XP and earlier OS platforms as setSuccess will be TRUE on Vista and later
{
// need to provide your own fallback mechanism such as the implementation below
// in essence the application will iterate through the user configured language list
WCHAR * next = userLanguagesMultiString;
while(!resContainer && *next != L'\0')
{
// convert the language name to an appropriate LCID
// DownlevelLocaleNameToLCID is available via standalone download package
// and is contained in Nlsdl.h / Nlsdl.lib
LCID nextLcid = DownlevelLocaleNameToLCID(next,DOWNLEVEL_LOCALE_NAME);
// then have LoadMUILibrary attempt to probe for the right .mui module
resContainer = LoadMUILibraryW(HELLO_MODULE_CONTRIVED_FILE_PATH,MUI_LANGUAGE_NAME,(LANGID)nextLcid);
// increment to the next language name in our list
size_t nextStrLen = 0;
if(SUCCEEDED(StringCchLengthW(next,LOCALE_NAME_MAX_LENGTH,&nextStrLen)))
next += (nextStrLen + 1);
else
break; // string is invalid - need to exit
}
// if the user configured list did not locate a module then try the languages associated with the system
if(!resContainer)
resContainer = LoadMUILibraryW(HELLO_MODULE_CONTRIVED_FILE_PATH,MUI_LANGUAGE_NAME,0);
}
if(!resContainer)
{
swprintf_s(displayBuffer,SUFFICIENTLY_LARGE_ERROR_BUFFER,L"FAILURE: Unable to load the resource container module, last error = %d.",GetLastError());
MessageBoxW(NULL,displayBuffer,L"HelloMUI ERROR!",MB_OK | MB_ICONERROR);
return 1; // exit
}
// 3. Application parses the resource container to find the appropriate item
WCHAR szHello[SUFFICIENTLY_LARGE_STRING_BUFFER];
if(LoadStringW(resContainer,HELLO_MUI_STR_0,szHello,SUFFICIENTLY_LARGE_STRING_BUFFER) == 0)
{
swprintf_s(displayBuffer,SUFFICIENTLY_LARGE_ERROR_BUFFER,L"FAILURE: Unable to load the resource string, last error = %d.",GetLastError());
MessageBoxW(NULL,displayBuffer,L"HelloMUI ERROR!",MB_OK | MB_ICONERROR);
FreeLibrary(resContainer);
return 1; // exit
}
// 4. Application presents the discovered resource to the user via UI
swprintf_s(displayBuffer,SUFFICIENTLY_LARGE_ERROR_BUFFER,L"%s MUI",szHello);
MessageBoxW(NULL,displayBuffer,L"HelloMUI",MB_OK | MB_ICONINFORMATION);
// 5. Application cleans up memory associated with the resource container after this item is no longer needed.
if(!FreeMUILibrary(resContainer))
{
swprintf_s(displayBuffer,SUFFICIENTLY_LARGE_ERROR_BUFFER,L"FAILURE: Unable to unload the resource container, last error = %d.",GetLastError());
MessageBoxW(NULL,displayBuffer,L"HelloMUI ERROR!",MB_OK | MB_ICONERROR);
return 1; // exit
}
return 0;
}
BOOL GetMyUserDefinedLanguages(WCHAR * langStr, DWORD langStrSize)
{
BOOL rtnVal = FALSE;
// very simple implementation - assumes that first 'langStrSize' characters of the
// L".\\langs.txt" file comprises a string of one or more languages
HANDLE langConfigFileHandle = CreateFileW(L".\\langs.txt", GENERIC_READ, 0,
NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if(langConfigFileHandle != INVALID_HANDLE_VALUE)
{
// clear out the input variables
DWORD bytesActuallyRead = 0;
if(ReadFile(langConfigFileHandle,langStr,langStrSize*sizeof(WCHAR),&bytesActuallyRead,NULL) && bytesActuallyRead > 0)
{
rtnVal = TRUE;
DWORD nullIndex = (bytesActuallyRead/sizeof(WCHAR) < langStrSize) ? bytesActuallyRead/sizeof(WCHAR) : langStrSize;
langStr[nullIndex] = L'\0';
}
CloseHandle(langConfigFileHandle);
}
return rtnVal;
}
BOOL ConvertMyLangStrToMultiLangStr(WCHAR * langStr, WCHAR * langMultiStr, DWORD langMultiStrSize)
{
BOOL rtnVal = FALSE;
size_t strLen = 0;
rtnVal = SUCCEEDED(StringCchLengthW(langStr,USER_CONFIGURATION_STRING_BUFFER*2,&strLen));
if(rtnVal && strLen > 0 && langMultiStr && langMultiStrSize > 0)
{
WCHAR * langMultiStrPtr = langMultiStr;
WCHAR * last = langStr + (langStr[0] == 0xFEFF ? 1 : 0);
WCHAR * context = last;
WCHAR * next = wcstok_s(last,L",; :",&context);
while(next && rtnVal)
{
// make sure you validate the user input
if(SUCCEEDED(StringCchLengthW(last,LOCALE_NAME_MAX_LENGTH,&strLen))
&& DownlevelLocaleNameToLCID(next,0) != 0)
{
langMultiStrPtr[0] = L'\0';
rtnVal &= SUCCEEDED(StringCchCatW(langMultiStrPtr,(langMultiStrSize - (langMultiStrPtr - langMultiStr)),next));
langMultiStrPtr += strLen + 1;
}
next = wcstok_s(NULL,L",; :",&context);
if(next)
last = next;
}
if(rtnVal && (langMultiStrSize - (langMultiStrPtr - langMultiStr))) // make sure there is a double null term for the multi-string
{
langMultiStrPtr[0] = L'\0';
}
else // fail and guard anyone whom might use the multi-string
{
langMultiStr[0] = L'\0';
langMultiStr[1] = L'\0';
}
}
return rtnVal;
}