(PHP 4 >= 4.0.4, PHP 5)
ctype_upper — Check for uppercase character(s)
Checks if all of the characters in the provided string, text, are uppercase characters.
The tested string.
Returns TRUE if every character in text is an uppercase letter in the current locale.
Example #1 A ctype_upper() example (using the default locale) 以上例程会输出：
<?php
$strings = array('AKLWC139', 'LMNSDO', 'akwSKWsm');
foreach ($strings as $testcase) {
if (ctype_upper($testcase)) {
echo "The string $testcase consists of all uppercase letters.
";
} else {
echo "The string $testcase does not consist of all uppercase letters.
";
}
}
?>
The string AKLWC139 does not consist of all uppercase letters.
The string LMNSDO consists of all uppercase letters.
The string akwSKWsm does not consist of all uppercase letters.
Note:
If an integer between -128 and 255 inclusive is provided, it is interpreted as the ASCII value of a single character (negative values have 256 added in order to allow characters in the Extended ASCII range). Any other integer is interpreted as a string containing the decimal digits of the integer.