GetStringTypeW

The GetStringTypeW function returns character-type information for the characters in the specified source string. For each character in the string, the function sets one or more bits in the corresponding 16-bit element of the output array. Each bit identifies a given character type, such as whether the character is a letter, a digit, or neither.

BOOL GetStringTypeW(
  DWORD dwInfoType,  // information-type options
  LPCWSTR lpSrcStr,  // pointer to source string
  int cchSrc,        // number of characters in string
  LPWORD lpCharType  // pointer to buffer for output
);

Parameters

dwInfoType
Specifies the type of character information the user wants to retrieve. The various types are divided into different levels (see the following Remarks section for a list of the information included in each type). This parameter can specify one of the following character type flags:
CT_CTYPE1 Retrieve character type information.
CT_CTYPE2 Retrieve bidirectional layout information.
CT_CTYPE3 Retrieve text processing information.

lpSrcStr
Pointer to the string for which character types are requested. If cchSrc is –1, the string is assumed to be null terminated. This must be a Unicode string.
cchSrc
Specifies the size, in characters, of the string pointed to by the lpSrcStr parameter. If this count includes a null terminator, the function returns character type information for the null terminator. If this value is –1, the string is assumed to be null terminated and the length is calculated automatically.
lpCharType
Pointer to an array of 16-bit values. The length of this array must be large enough to receive one 16-bit value for the number of characters specified in the cchSrc parameter. When the function returns, this array contains one word corresponding to each Unicode character in the source string.

Return Values

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero. To get extended error information, call GetLastError. GetLastError may return one of the following error codes:

ERROR_INVALID_FLAGS
ERROR_INVALID_PARAMETER

Remarks

Note that the GetStringTypeA function has one more parameter than the GetStringTypeW function: GetStringTypeA has a first parameter that is an LCID named Locale. This parameter does not exist in the GetStringTypeW function. Because of that parameter difference, an application cannot automatically invoke the proper A or W version of GetStringType* through the use of the #define UNICODE switch. An application can circumvent this limitation by using GetStringTypeEx; it is the recommended Win32 function.

The lpSrcStr and lpCharType pointers must not be the same. If they are the same, the function fails and GetLastError returns ERROR_INVALID_PARAMETER.

The character-type bits are divided into several levels. The information for one level can be retrieved by a single call to this function. Each level is limited to 16 bits of information so that the other mapping routines, which are limited to 16 bits of representation per character, can also return character-type information.

The character types supported by this function include the following.

Ctype 1
These types support ANSI C and POSIX (LC_CTYPE) character-typing functions. A combination of these values is returned in the array pointed to by the lpCharType parameter when the dwInfoType parameter is set to CT_CTYPE1.
Name Value Meaning
C1_UPPER 0x0001 Uppercase
C1_LOWER 0x0002 Lowercase
C1_DIGIT 0x0004 Decimal digits
C1_SPACE 0x0008 Space characters
C1_PUNCT 0x0010 Punctuation
C1_CNTRL 0x0020 Control characters
C1_BLANK 0x0040 Blank characters
C1_XDIGIT 0x0080 Hexadecimal digits
C1_ALPHA 0x0100 Any linguistic character: alphabetic, syllabary, or ideographic

The following character types are either constant or computable from basic types and do not need to be supported by this function.

Type Description
Alphanumeric Alphabetic characters and digits (C1_ALPHA and C1_DIGIT)
Printable Graphic characters and blanks (all C1_* types except C1_CNTRL)

Ctype 2
These types support proper layout of Unicode text. The direction attributes are assigned so that the bidirectional layout algorithm standardized by Unicode produces accurate results. These types are mutually exclusive. For more information about the use of these attributes, see The Unicode Standard: Worldwide Character Encoding, Volumes 1 and 2, Addison Wesley Publishing Company: 1991, 1992, ISBN 0201567881.
Name Value Meaning
Strong
C2_LEFTTORIGHT 0x0001 Left to right
C2_RIGHTTOLEFT 0x0002 Right to left
Weak
C2_EUROPENUMBER 0x0003 European number, European digit
C2_EUROPESEPARATOR 0x0004 European numeric separator
C2_EUROPETERMINATOR 0x0005 European numeric terminator
C2_ARABICNUMBER 0x0006 Arabic number
C2_COMMONSEPARATOR 0x0007 Common numeric separator
Neutral
C2_BLOCKSEPARATOR 0x0008 Block separator
C2_SEGMENTSEPARATOR 0x0009 Segment separator
C2_WHITESPACE 0x000A White space
C2_OTHERNEUTRAL 0x000B Other neutrals
Not applicable
C2_NOTAPPLICABLE 0x0000 No implicit directionality (for example, control codes)

Ctype 3
These types are intended to be placeholders for extensions to the POSIX types required for general text processing or for the standard C library functions. A combination of these values is returned when dwInfoType is set to CT_CTYPE3.
Name Value Meaning
C3_NONSPACING 0x0001 Nonspacing mark
C3_DIACRITIC 0x0002 Diacritic nonspacing mark
C3_VOWELMARK 0x0004 Vowel nonspacing mark
C3_SYMBOL 0x0008 Symbol
C3_KATAKANA 0x0010 Katakana character
C3_HIRAGANA 0x0020 Hiragana character
C3_HALFWIDTH 0x0040 Half-width character
C3_FULLWIDTH 0x0080 Full-width character
C3_IDEOGRAPH 0x0100 Ideographic character
C3_KASHIDA 0x0200 Arabic Kashida character
C3_LEXICAL 0x0400 Punctuation which is counted as part of the word (Kashida, hyphen, feminine/masculine ordinal indicators, equal sign, and so forth)
C3_ALPHA 0x8000 All linguistic characters (alphabetic, syllabary, and ideographic)
Not applicable
C3_NOTAPPLICABLE 0x0000 Not applicable

QuickInfo

  Windows NT: Requires version 3.1 or later.
  Windows: Unsupported.
  Windows CE: Unsupported.
  Header: Declared in winnls.h.
  Import Library: Use kernel32.lib.

See Also

String Manipulation Overview, String Manipulation Functions, GetLocaleInfo, GetStringTypeA, GetStringTypeEx