PHP函数：ctype_digit

 (PHP 4 >= 4.0.4)
功能说明：Check for numeric character(s)
Description
bool ctype_digit ( string text)
Returns TRUE if every character in text is a decimal digit, FALSE otherwise.
例子 1. A ctype_digit() example
<?php $strings = array('1820.20', '10002', 'wsl!12'); foreach ($strings as $testcase) {
if (ctype_digit($testcase)) {
echo "The string $testcase consists of all digits.\n";
} else {
echo "The string $testcase does not consist of all digits.\n";
}
} ?>
This example will output :
The string 1820.20 does not consists of all digits. The string 10002 consists of all digits. The string wsl!12 does not consists of all digits.
PHP函数：ctype_xdigit
(PHP 4 >= 4.0.4)
功能说明：Check for character(s) representing a hexadecimal digit
Description
bool ctype_xdigit ( string text)
Returns TRUE if every character in text is a hexadecimal 'digit', that is a decimal digit or a character from [A-Fa-f] , FALSE otherwise.
例子 1. A ctype_xdigit() example
<?php $strings = array('AB10BC99', 'AR1012', 'ab12bc99'); foreach ($strings as $testcase) {
if (ctype_xdigit($testcase)) {
echo "The string $testcase consists of all hexadecimal digits.\n";
} else {
echo "The string $testcase does not consist of all hexadecimal digits.\n";
}
} ?>
This example will output :
The string AB10BC99 consists of all hexadecimal digits. The string AR1012 does not consist of all hexadecimal digits. The string ab12bc99 consists of all hexadecimal digits.
ctype_alnum
(PHP 4 >= 4.0.4, PHP 5)
ctype_alnum -- Check for alphanumeric character(s)
说明
bool ctype_alnum ( string text )
Checks if all of the characters in the provided string, text, are alphanumeric. In the standard C locale letters are just [A-Za-z] and the function is equivalent to preg_match('/^[a-z0-9]*$/i', $text).
参数
text
The tested string.
返回值
Returns TRUE if