?function?create_uuid($prefix?=?""){?//可以指定前綴

????$str?= md5(uniqid(mt_rand(), true));??

????$uuid?=?substr($str,0,8) .?'-';??

????$uuid?.=?substr($str,8,4) .?'-';??

????$uuid?.=?substr($str,12,4) .?'-';??

????$uuid?.=?substr($str,16,4) .?'-';??

????$uuid?.=?substr($str,20,12);??

????return?$prefix?.?$uuid;

}

echo?create_uuid();