FindNLSString function (winnls.h)

Article
10/13/2021

Locates a Unicode string (wide characters) or its equivalent in another Unicode string for a locale specified by identifier.

Caution Because strings with very different binary representations can compare as identical, this function can raise certain security concerns. For more information, see the discussion of comparison functions in Security Considerations: International Features.

Note For interoperability reasons, the application should prefer the FindNLSStringEx function because Microsoft is migrating toward the use of locale names instead of locale identifiers for new locales. Although FindNLSString supports custom locales, most applications should use FindNLSStringEx for this type of support.

Syntax

int FindNLSString(
  [in]            LCID    Locale,
  [in]            DWORD   dwFindNLSStringFlags,
  [in]            LPCWSTR lpStringSource,
  [in]            int     cchSource,
  [in]            LPCWSTR lpStringValue,
  [in]            int     cchValue,
  [out, optional] LPINT   pcchFound
);

Parameters

[in] Locale

Locale identifier that specifies the locale. You can use the MAKELCID macro to create an identifier or use one of the following predefined values.

Windows Vista and later: The following custom locale identifiers are also supported.

[in] dwFindNLSStringFlags

Flags specifying details of the find operation. For detailed definitions, see the dwFindNLSStringFlags parameter of FindNLSStringEx.

[in] lpStringSource

Pointer to the source string, in which the function searches for the string specified by lpStringValue.

[in] cchSource

Size, in characters excluding the terminating null character, of the string indicated by lpStringSource. The application cannot specify 0 or any negative number other than -1 for this parameter. The application specifies -1 if the source string is null-terminated and the function should calculate the size automatically.

[in] lpStringValue

Pointer to the search string, for which the function searches in the source string.

[in] cchValue

Size, in characters excluding the terminating null character, of the string indicated by lpStringValue. The application cannot specify 0 or any negative number other than -1 for this parameter. The application specifies -1 if the search string is null-terminated and the function should calculate the size automatically.

[out, optional] pcchFound

Pointer to a buffer containing the length of the string that the function finds. For details, see the pcchFound parameter of FindNLSStringEx.

Return value

Returns a 0-based index into the source string indicated by lpStringSource if successful. In combination with the value in pcchFound, this index provides the exact location of the entire found string in the source string. A return value of 0 is an error-free index into the source string, and the matching string is in the source string at offset 0.

The function returns -1 if it does not succeed. To get extended error information, the application can call GetLastError, which can return one of the following error codes:

ERROR_INVALID_FLAGS. The values supplied for flags were not valid.
ERROR_INVALID_PARAMETER. Any of the parameter values was invalid.
ERROR_SUCCESS. The action completed successfully but yielded no results.

Remarks

See Remarks for FindNLSStringEx.

Requirements

Requirement	Value
Minimum supported client	Windows Vista [desktop apps only]
Minimum supported server	Windows Server 2008 [desktop apps only]
Target Platform	Windows
Header	winnls.h (include Windows.h)
Library	Kernel32.lib
DLL	Kernel32.dll