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Chapter 6 - Script Manager / Script Manager Reference

Routines

Analyzing Characters

This section describes the functions CharacterByteType, CharacterType, and FillParseTable, which give you information about a character or group of characters, specified by character code:

• The CharacterByteType function identifies a byte in a text buffer as a 1-byte character or as the first or second byte of a 2-byte character.
• The CharacterType function returns specific information about the character at a particular byte offset.
• The FillParseTable function fills a 256-byte table that indicates, for each possible byte value, whether it is the first byte of a 2-byte character.

The script system associated with the character you wish to examine must be enabled in order for any of these three routines to provide useful information. For example, if only the Roman script system is available and you attempt to identify a byte in a run of 2-byte characters, the CharacterByteType function returns 0, indicating that the byte is a 1-byte character.

1-byte script systems

For 1-byte script systems, the character-type tables reside in the string-manipulation ('itl2') resource and reflect region-specific or language-specific differences in uppercase conventions. The CharacterType function gets the tables from the string-manipulation resource using the GetIntlResource function.

2-byte script systems

For 2-byte script systems, the character-type tables reside in the encoding/rendering ('itl5') resource, not the string-manipulation resource. Whenever you call CharacterByteType, CharacterType, or FillParseTable, the necessary character-set encoding information is taken from the encoding/rendering resource. You cannot use the GetIntlResource function to access 2-byte character-type
tables directly.

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Subtopics

CharacterByteType

CharacterType

FillParseTable