ctype_upper()

(PHP 4 >= 4.0.4, PHP 5, PHP 7)

做大写字母检测

说明

ctype_upper(string $text): bool

检查string和$text里面的字符是不是都是大写字母。

参数

$text: 需要被测试的字符串。

返回值

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。

范例

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.

注释

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.

参见

ctype_alpha()做纯字符检测
ctype_lower()做小写字符检测
setlocale()设置地区信息

Underscores in the string will result in false, so you have to remove them first.

// 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