php 生成不带横杠的UUID

 1     /**
 2      * 生成不带横杠的UUID
 3      * @return string
 4      */
 5     public static function genuuid()
 6     {
 7         return sprintf('%04x%04x%04x%04x%04x%04x%04x%04x',
 8             // 32 bits for "time_low"
 9             mt_rand(0, 0xffff), mt_rand(0, 0xffff),
10 
11             // 16 bits for "time_mid"
12             mt_rand(0, 0xffff),
13 
14             // 16 bits for "time_hi_and_version",
15             // four most significant bits holds version number 4
16             mt_rand(0, 0x0fff) | 0x4000,
17 
18             // 16 bits, 8 bits for "clk_seq_hi_res",
19             // 8 bits for "clk_seq_low",
20             // two most significant bits holds zero and one for variant DCE1.1
21             mt_rand(0, 0x3fff) | 0x8000,
22 
23             // 48 bits for "node"
24             mt_rand(0, 0xffff), mt_rand(0, 0xffff), mt_rand(0, 0xffff)
25         );
26     }