我需要从这些字母生成代码
$a = array(
'B','C','D','F','G','H','J','K','L','M','N','O',
'P','Q','R','S','T','V','W','X','Y','Z','1','2',
'3','4','5','6','7','8','9','0'
);
但是有两个条件:每个代码必须是唯一的并且包含10个字母。我不想随意,因为效率低下。相反,我想要每个字母,例如:
等等..有什么想法吗?
答案 0 :(得分:4)
我认为你真正想要的是一个序列号列表(因此根本不是随机的),而是一个相当不自然的基础系统。因此BBBBBBBBB
为0
,而BBBBBBBC
为1
。这并不难,但显然你必须自己编写代码。这样的事情可能有用:
function generate($num) {
$num = base_convert($num, 10, 32); // convert the number to base 32
$num = str_pad($num, 10, "0", STR_PAD_LEFT); // pad it with zeros to the left
$num = str_replace(array(
'0','1','2','3','4','5','6','7','8','9','a','b',
'c','d','e','f','g','h','i','j','k','l','m','n',
'o','p','q','r','s','t','u','v'
), array(
'B','C','D','F','G','H','J','K','L','M','N','O',
'P','Q','R','S','T','V','W','X','Y','Z','1','2',
'3','4','5','6','7','8','9','0'
), $num); // replace the normal characters with your custom array
echo $num, "\n";
}
for ($i = 0; $i < 10; $i++) generate($i);
显然,您可以将10
语句中的for
更改为您喜欢的任何内容,然后插入数据库而不是echo
。显然,160万条记录需要一些时间来生成。
上面的代码给出了以下输出:
BBBBBBBBBB
BBBBBBBBBC
BBBBBBBBBD
BBBBBBBBBF
BBBBBBBBBG
BBBBBBBBBH
BBBBBBBBBJ
BBBBBBBBBK
BBBBBBBBBL
BBBBBBBBBM
答案 1 :(得分:3)
<?php
$length = 3;
$letters = str_split("ABC"); // define your dictionary here
$index = array_fill(0, $length, 0);
$key = $length - 1;
while(true) {
$code = "";
for($i=0;$i<$length;$i++) {
$code .= $letters[$index[$i]];
}
echo $code ."<br/>"; // output code
$index[$key]++;
while(!isset($letters[$index[$key]])) {
$index[$key] = 0;
$key--;
if($key < 0) {
break 2;
}
$index[$key]++;
}
$key = $length - 1;
}
示例:
答案 2 :(得分:1)
<?php
$a = array(
'B','C','D','F','G','H','J','K','L','M','N','O',
'P','Q','R','S','T','V','W','X','Y','Z','1','2',
'3','4','5','6','7','8','9','0'
);
function key_increment (&$symbols, $position = null)
{
global $a;
if ($position === null) $position = count($symbols) - 1;
if ($position == -1) return;
$index = $symbols[$position];
$index ++;
if (!isset($a[$index])) {
$v = 0;
key_increment ($symbols, $position-1);
}
$symbols[$position] = $value;
}
function generate($length, $total)
{
global $a;
$symbols = array_fill(0, $length, 0);
for ($i = 0; $i < $total; $i ++) {
$code = '';
foreach ($symbols as $index) {
$code .= $a[$index];
}
echo $code;
echo '<br />';
key_increment($symbols);
}
}
generate(3, 100);
答案 3 :(得分:0)
你最好只使用uniqid,尤其是看你说你将产生160万个代码。如果你担心这种情况,只需使用strtoupper()
echo strtoupper(uniqid());
生成所有这些并插入它们将花费相当多的时间。