如何在 PHP 中按字母顺序对数组值排序

### Answer: Use the PHP sort() and rsort() function
The PHP `sort()` and `rsort()` functions can be used for sorting [numeric or indexed arrays](http://www.bixiaguangnian.com/manual/php7/3974.html "numeric or indexed arrays"). The following sections will show you how these functions basically work:

### Sorting Numeric Arrays in Ascending Order
You can use the `sort()` function for sorting the numeric array elements or values alphabetically or numerically in the ascending order. Let's try out an example to see how it works:

```php
<?php
$text = array("Sky", "Cloud", "Birds", "Rainbow", "Moon");
$numbers = array(1, 2, 3.5, 5, 8, 10);
 
// Sorting the array of string
sort($text);
print_r($text);
echo "<br>";
 
// Sorting the array of numbers
sort($numbers);
print_r($numbers);
?>
```
### Sorting Numeric Arrays in Descending Order
You can use the `rsort()` function for sorting the numeric array elements or values alphabetically or numerically in the descending order. Let's check out an example:

```php
<?php
$text = array("Sky", "Cloud", "Birds", "Rainbow", "Moon");
$numbers = array(1, 2, 3.5, 5, 8, 10);
 
// Sorting the array of string
rsort($text);
print_r($text);
echo "<br>";
 
// Sorting the array of numbers
rsort($numbers);
print_r($numbers);
?>
```