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 every character in text is either a letter or a digit, FALSE otherwise.
范例
例子 1. A ctype_alnum() example (using the default locale)
<?php
$strings = array('AbCd1zyZ9', 'foo!#$bar');
foreach ($strings as $testcase) {
if (ctype_alnum($testcase)) {
echo "The string $testcase consists of
all letters or digits.\n";
} else {
echo "The string $testcase does not
consist of all letters or digits.\n";
}
}
?>
上例将输出：
The string AbCd1zyZ9 consists of all letters or digits. The string foo!#$bar does not consists of all letters or digits.
