ctype_alpha
    (PHP 4 >= 4.0.4, PHP 5)
ctype_alpha -- Check for alphabetic character(s)
Description
bool 
ctype_alpha ( string text )
   Checks if all of the characters in the provided string,
   text, are alphabetic.
   In the standard C locale letters are just 
   [A-Za-z] and ctype_alpha() is 
   equivalent to (ctype_upper($text) || ctype_lower($text))
   if $text is just a single character, but other languages have letters that 
   are considered neither upper nor lower case.
  
Return Values
   Returns TRUE if every character in text is 
   a letter from the current locale, FALSE otherwise.
  
Examples
   
Example 1. A ctype_alpha() example (using the default locale) 
<?php $strings = array('KjgWZC', 'arf12'); foreach ($strings as $testcase) {     if (ctype_alpha($testcase)) {         echo "The string $testcase consists of all letters.\n";     } else {         echo "The string $testcase does not consist of all letters.\n";     } } ?>
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 The above example will output: The string KjgWZC consists of all letters.
The string arf12 does not consists of all letters.  |  
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