PHP随机生成token

[', ']', 'h', ';', 'W', '.',
						'/', '|', ':', '1', 'E', 'L', '4', '&', '6', '7', '#', '9', 'a',
						'A', 'b', 'B', '~', 'C', 'd', '>', 'e', '2', 'f', 'P', 'g', ')',
						'?', 'H', 'i', 'X', 'U', 'J', 'k', 'r', 'l', '3', 't', 'M', 'n',
						'=', 'o', '+', 'p', 'F', 'q', '!', 'K', 'R', 's', 'c', 'm', 'T',
						'v', 'j', 'u', 'V', 'w', ',', 'x', 'I', '$', 'Y', 'z', '*'
				);
				# Array indice friendly number of chars;
				$numChars = count($chars) - 1; $token = '';
				# Create random token at the specified length
				for ( $i=0; $i<$len; $i++ )
						$token .= $chars[ mt_rand(0, $numChars) ];
				# Should token be run through md5?
				if ( $md5 ) {
						# Number of 32 char chunks
						$chunks = ceil( strlen($token) / 32 ); $md5token = '';
						# Run each chunk through md5
						for ( $i=1; $i<=$chunks; $i++ )
								$md5token .= md5( substr($token, $i * 32 - 32, 32) );
						# Trim the token
						$token = substr($md5token, 0, $len);
				} return $token;
		}
		//生成的32位随机数
		echo genToken()
?>