php man page for ctype_alnum

CTYPE_ALNUM(3)								 1							    CTYPE_ALNUM(3)

ctype_alnum - Check for alphanumeric character(s)

SYNOPSIS
       bool ctype_alnum (string  $text)

DESCRIPTION
	Checks if all of the characters in the provided string, $text, are alphanumeric.

PARAMETERS
	      o $text
		- The tested string.

RETURN VALUES
	Returns TRUE if every character in $text is either a letter or a digit, FALSE otherwise.

EXAMPLES
       Example #1

	      A ctype_alnum(3) example (using the default locale)

	      <?php
	      $strings = array('AbCd1zyZ9', 'foo!#$bar');
	      foreach ($strings as $testcase) {
		  if (ctype_alnum($testcase)) {
		      echo "The string $testcase consists of all letters or digits.
";
		  } else {
		      echo "The string $testcase does not consist of all letters or digits.
";
		  }
	      }
	      ?>

	      The above example will output:

	      The string AbCd1zyZ9 consists of all letters or digits.
	      The string foo!#$bar does not consist of all letters or digits.

NOTES
       Note

	       If an integer between -128 and 255 inclusive is provided, it is interpreted as the ASCII value of a single character (negative val-
	      ues have 256 added in order to allow characters in the Extended ASCII range). Any other integer is interpreted as a string  contain-
	      ing the decimal digits of the integer.

SEE ALSO
       ctype_alpha(3), ctype_digit(3), setlocale(3).

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