std::isalpha
Da cppreference.com.
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Elemento definito nell'header <cctype> | ||
int isalpha(int ch ); | ||
Controlla se il carattere è dato un carattere alfabetico in base alle impostazioni internazionali attualmente installato C. Nella località di default, questa funzione restituisce true per le lettere e
ABCDEFGHIJKLMNOPQRSTUVWXYZ
abcdefghijklmnopqrstuvwxyz
.Original:
Checks if the given character is an alphabetic character according to the currently installed C locale. In the default locale, this function returns true for the letters
ABCDEFGHIJKLMNOPQRSTUVWXYZ
and abcdefghijklmnopqrstuvwxyz
.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
Indice |
[modifica]Parametri
ch | - | carattere Original: character The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
[modifica]Valore di ritorno
Valore diverso da zero (true) se il carattere è un carattere alfabetico,
0
(false) altrimenti.Original:
Non-zero value (true) if the character is an alphabetic character,
0
(false) otherwise.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
[modifica]Esempio
#include <iostream>#include <cctype> #include <clocale> int main(){char c ='\xdf';// German letter ß in ISO-8859-1 std::cout<<"isalpha(\'\\xdf\', default C locale) returned "<<std::boolalpha<<(bool)std::isalpha(c)<<'\n'; std::setlocale(LC_ALL, "de_DE.iso88591");std::cout<<"isalpha(\'\\xdf\', ISO-8859-1 locale) returned "<<std::boolalpha<<(bool)std::isalpha(c)<<'\n'; }
Output:
isalpha('\xdf', default C locale) returned false isalpha('\xdf', ISO-8859-1 locale) returned true
[modifica]Vedi anche
Verifica se un carattere è classificato come alfabetico da un locale Original: checks if a character is classified as alphabetic by a locale The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (funzione di modello) | |
Verifica se un carattere esteso è alfabetico Original: checks if a wide character is alphabetic The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (funzione) | |
C documentation for isalpha |
ASCII values (hex) | characters | isalpha | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0 - 8 | 0x00-0x08 | control codes (NUL , etc.) | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
9 | 0x09 | tab (\t ) | ≠0 | 0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
10 - 13 | 0x0A-0x0D | whitespaces (\n ,\v ,\f ,\r ) | ≠0 | 0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
14 - 31 | 0x0E-0x1F | control codes | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
32 | 0x20 | space | 0 | ≠0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
33 - 47 | 0x21-0x2F | !"#$%&'()*+,-./ | 0 | ≠0 | 0 | 0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 |
48 - 57 | 0x30-0x39 | 0123456789 | 0 | ≠0 | 0 | 0 | ≠0 | 0 | ≠0 | 0 | 0 | 0 | ≠0 | ≠0 |
58 - 64 | 0x3a-0x40 | :;<=>?@ | 0 | ≠0 | 0 | 0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 |
65 - 70 | 0x41-0x46 | ABCDEF | 0 | ≠0 | 0 | 0 | ≠0 | 0 | ≠0 | ≠0 | ≠0 | 0 | 0 | ≠0 |
71 - 90 | 0x47-0x5A | GHIJKLMNOPQRSTUVWXYZ | 0 | ≠0 | 0 | 0 | ≠0 | 0 | ≠0 | ≠0 | ≠0 | 0 | 0 | 0 |
91 - 96 | 0x5B-0x60 | [\]^_` | 0 | ≠0 | 0 | 0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 |
97 -102 | 0x61-0x66 | abcdef | 0 | ≠0 | 0 | 0 | ≠0 | 0 | ≠0 | ≠0 | 0 | ≠0 | 0 | ≠0 |
103-122 | 0x67-0x7A | ghijklmnopqrstuvwxyz | 0 | ≠0 | 0 | 0 | ≠0 | 0 | ≠0 | ≠0 | 0 | ≠0 | 0 | 0 |
123-126 | 0x7B-0x7E | {|}~ | 0 | ≠0 | 0 | 0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 |
127 | 0x7F | backspace character (DEL ) | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |