ctype_upper
    (PHP 4 >= 4.0.4, PHP 5)
ctype_upper -- Check for uppercase character(s)
Description
bool 
ctype_upper ( string text )
   Checks if all of the characters in the provided string,
   text, are uppercase characters.
  
Return Values
   Returns TRUE if every character in text is 
   an uppercase letter in the current locale.
  
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";     } } ?>
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 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.  |  
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