这是我最终版本的 GUIDv4 函数(基于这里其他人的作品),它应该在所有平台上都能正常工作,如果其他平台不支持,则优雅地回退到安全性较低的版本...
<?php
function GUIDv4 ($trim = true)
{
if (function_exists('com_create_guid') === true) {
if ($trim === true)
return trim(com_create_guid(), '{}');
else
return com_create_guid();
}
if (function_exists('openssl_random_pseudo_bytes') === true) {
$data = openssl_random_pseudo_bytes(16);
$data[6] = chr(ord($data[6]) & 0x0f | 0x40); $data[8] = chr(ord($data[8]) & 0x3f | 0x80); return vsprintf('%s%s-%s-%s-%s-%s%s%s', str_split(bin2hex($data), 4));
}
mt_srand((double)microtime() * 10000);
$charid = strtolower(md5(uniqid(rand(), true)));
$hyphen = chr(45); $lbrace = $trim ? "" : chr(123); $rbrace = $trim ? "" : chr(125); $guidv4 = $lbrace.
substr($charid, 0, 8).$hyphen.
substr($charid, 8, 4).$hyphen.
substr($charid, 12, 4).$hyphen.
substr($charid, 16, 4).$hyphen.
substr($charid, 20, 12).
$rbrace;
return $guidv4;
}
?>