(PHP 4 >= 4.0.4, PHP 5, PHP 7)
ctype_upper — 做大写字母检测
text需要被测试的字符串。
在当前语言环境下，如果 text 里面的每个字符都是大写字母，就返回 TRUE。
Example #1 一个 ctype_upper() 例子 （使用当前默认语言环境）
<?php
$strings = array('AKLWC139', 'LMNSDO', 'akwSKWsm');
foreach ($strings as $testcase) {
if (ctype_upper($testcase)) {
echo "The string $testcase consists of all uppercase letters.\n";
} else {
echo "The string $testcase does not consist of all uppercase letters.\n";
}
}
?>
以上例程会输出：
The string AKLWC139 does not consist of all uppercase letters. The string LMNSDO consists of all uppercase letters. The string akwSKWsm does not consist of all uppercase letters.
Note:
如果给出一个 -128 到 255 之间(含)的整数, 将会被解释为该值对应的ASCII字符 (负值将加上 256 以支持扩展ASCII字符). 其它整数将会被解释为该值对应的十进制字符串.
// after screwing around with function.ctype-upper
// I found this simple solution
if (strtolower($string) != $string)// its so simple!
{
echo "uppercase letters found in $string";
}
source: http://stackoverflow.com/questions/4426327/how-to-detect-if-string-contains-1-uppercase-letter-in-php
Underscores in the string will result in false, so you have to remove them first.