简单判断函数总结

inline bool IsSpace(Char c)  
// Space, tabulation, line feed or return  
{  
    return(c == TEXT(' ') || c == TEXT('\t') || c == TEXT('\r') || c == TEXT('\n'));  
}  

inline bool IsAlpha(Char c)  
// [a-zA-Z]  
{  
    return((c >= TEXT('a') && c <= TEXT('z')) || (c >= TEXT('A') && c <= TEXT('Z')));  
}  

inline bool IsDigit(Char c)  
// For the moment, recognize only Basic Latin  
// [0-9]  
{  
    return(c >= TEXT('0') && c <= TEXT('9'));  
}  

inline bool IsHexDigit(Char c)  
// [0-9a-fA-F]  
{  
    return(IsDigit(c) || (c >= TEXT('a') && c <= TEXT('f')) || (c >= TEXT('A') && c <= TEXT('F')));  
}  

inline int HexDigitValue(Char c)  
// [0-9a-fA-F]  
{  
    return((c >= TEXT('0') && c <= TEXT('9')) ? c - TEXT('0')  
        : ((c >= TEXT('a') && c <= TEXT('f')) ? c - TEXT('a') + 10  
        : c - TEXT('A') + 10));  

}  

inline bool IsAlphaDigit(Char c)  
// [a-zA-Z0-9]  
{  
    return(IsAlpha(c) || IsDigit(c));  
}  

inline bool IsLetter(Char c_)  
// For the moment, recognize only Basic Latin and Latin-1 Supplement  
{  
    // if c is signed, c >= 0xD8 is always false,  so cast it  
    unsigned char c = c_;  

    return  
        (  
        (c >= 0x41 && c <= 0x5A) || // [A-Z]  
        (c >= 0x61 && c <= 0x7A) || // [a-z]  
        (c >= 0xC0 && c <= 0xD6) || // Latin-1 Supplement  
        (c >= 0xD8 && c <= 0xF6) || // "  
        (c >= 0xF8 && c <= 0xFF)    // "  
        );  
}
inline Char LowCase(Char c)  
{  
    return(c >= TEXT('A') && c <= TEXT('Z') ? static_cast<char></char>(c - TEXT('A') + TEXT('a')) : c);  
}  

inline bool IsNameChar(Char c)  
// [4] NameChar ::=  Letter | Digit | '.' | '-' | '_' | ':' | CombiningChar | Extender   
{  
    return  
        (  
        IsLetter(c) || IsDigit(c) ||  
        c == TEXT('.') || c == TEXT('-') || c == TEXT('_') || c == TEXT(':') ||  
        IsCombiningChar(c) || IsExtender(c)  
        );  
}