uniqid()返回的结果类似于'492607b0ee414'。我希望得到类似于TinyURL提供的'64k8ra'的字符串，越短越好。唯一的要求是它不应该有明显的顺序，并且应该比看起来像随机数字序列的字符更漂亮。字母比数字更受欢迎，理想情况下不会混合大小写字母。由于条目数量不会很多（最多10000个左右），碰撞的风险并不是很大。
欢迎任何建议。function createRandomString($length)
{
$random = mt_rand(0, (1 << ($length << 2)) - 1);
return dechex($random);
}
如果您需要字符串在任何情况下具有精确的长度，请使用零填充十六进制数：
function createRandomString($length)
{
$random = mt_rand(0, (1 << ($length << 2)) - 1);
$number = dechex($random);
return str_pad($number, $length, '0', STR_PAD_LEFT);
}
$length <= 8，而PHP的限制应该是4,294,967,295。mt_rand()，在32位系统上至少应该是2,147,483,647。回到主题 - 直觉上的do { (generate ID) } while { (id is not uniqe) } (insert id)有一个缺点和一个可能的缺陷，这可能会让你直接陷入黑暗中...
public static function generateCode($length = 6)
{
$az = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
$azr = rand(0, 51);
$azs = substr($az, $azr, 10);
$stamp = hash('sha256', time());
$mt = hash('sha256', mt_rand(5, 20));
$alpha = hash('sha256', $azs);
$hash = str_shuffle($stamp . $mt . $alpha);
$code = ucfirst(substr($hash, $azr, $length));
return $code;
}
10个字符：
substr(uniqid(),-10);
5个二进制字符：
hex2bin( substr(uniqid(),-10) );
8个base64字符：
base64_encode( hex2bin( substr(uniqid(),-10) ) );
function rand_str($len = 12, $type = '111', $add = null) {
$rand = ($type[0] == '1' ? 'abcdefghijklmnpqrstuvwxyz' : '') .
($type[1] == '1' ? 'ABCDEFGHIJKLMNPQRSTUVWXYZ' : '') .
($type[2] == '1' ? '123456789' : '') .
(strlen($add) > 0 ? $add : '');
if(empty($rand)) $rand = sha1( uniqid(mt_rand(), true) . uniqid( uniqid(mt_rand(), true), true) );
return substr(str_shuffle( str_repeat($rand, 2) ), 0, $len);
}
目前最佳答案：给定唯一数据库ID，生成最小唯一“哈希”字符串 - PHP解决方案，无需第三方库。
以下是代码：
<?php
/*
THE FOLLOWING CODE WILL PRINT:
A database_id value of 200 maps to 5K
A database_id value of 1 maps to 1
A database_id value of 1987645 maps to 16LOD
*/
$database_id = 200;
$base36value = dec2string($database_id, 36);
echo "A database_id value of 200 maps to $base36value\n";
$database_id = 1;
$base36value = dec2string($database_id, 36);
echo "A database_id value of 1 maps to $base36value\n";
$database_id = 1987645;
$base36value = dec2string($database_id, 36);
echo "A database_id value of 1987645 maps to $base36value\n";
// HERE'S THE FUNCTION THAT DOES THE HEAVY LIFTING...
function dec2string ($decimal, $base)
// convert a decimal number into a string using $base
{
//DebugBreak();
global $error;
$string = null;
$base = (int)$base;
if ($base < 2 | $base > 36 | $base == 10) {
echo 'BASE must be in the range 2-9 or 11-36';
exit;
} // if
// maximum character string is 36 characters
$charset = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
// strip off excess characters (anything beyond $base)
$charset = substr($charset, 0, $base);
if (!ereg('(^[0-9]{1,50}$)', trim($decimal))) {
$error['dec_input'] = 'Value must be a positive integer with < 50 digits';
return false;
} // if
do {
// get remainder after dividing by BASE
$remainder = bcmod($decimal, $base);
$char = substr($charset, $remainder, 1); // get CHAR from array
$string = "$char$string"; // prepend to output
//$decimal = ($decimal - $remainder) / $base;
$decimal = bcdiv(bcsub($decimal, $remainder), $base);
} while ($decimal > 0);
return $string;
}
?>
Random::alphaLowercaseString(6)来获取，或者根据你的需要选择长度为 8 或 10。 - caw