Check for uppercase character(s)

# ctype_upper

(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)

ctype_upper — Check for uppercase character(s)

### Description

ctype_upper(mixed `$text`): bool

Checks if all of the characters in the provided string, `text`, are uppercase characters.

### Parameters

`text`

  The tested string.

  > Note:

  > If an int 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.

  Warning

  As of PHP 8.1.0, passing a non-string argument is deprecated. In the future, the argument will be interpreted as a string instead of an ASCII codepoint. Depending on the intended behavior, the argument should either be cast to string or an explicit call to chr() should be made.

### Return Values

Returns `true` if every character in `text` is an uppercase letter in the current locale. When called with an empty string the result will always be `false`.

### Examples

Example #1 A ctype_upper() example (using the default locale)

`<?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";
}
}
?>`

The above example will output:

    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.

### See Also

- ctype_alpha() - Check for alphabetic character(s)
- ctype_lower() - Check for lowercase character(s)
- setlocale() - Set locale information
- IntlChar::isupper() - Check if code point has the general category "Lu" (uppercase letter)

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