随机数组不能像预期的那样工作

Question

I'm trying to create an array and display some random values. I'm using the following code:

$range = range(10,31);
$rand = array_rand($range,5);
shuffle($rand);

foreach ($rand as $number) {
  $number = (str_pad($number, 2, "0", STR_PAD_LEFT));
  echo $number." ";
} 

I want to generate numbers between 10 and 31 and display 5 of them, but my code still generating numbers between 00 and 31. Why this is happening?

Answer 1

Since array_rand() returns keys, not values, you have to use them as indexes into the original $range array.

foreach ($rand as $index) {
  $number = (str_pad($range[$index], 2, "0", STR_PAD_LEFT));
  echo $number." ";
}

You could also just call shuffle($range) and then iterate over the first 5 elements of $range.