PHP全局函数与工具类设计

PHP全局函数与工具类设计

全局函数和工具类在项目中很常用。好的设计让工具代码更易用。今天说说PHP中全局函数和工具类的设计。

辅助函数文件。

```php
// helpers.php

function str_limit(string $value, int $limit = 100, string $end = '...'): string
{
if (mb_strlen($value) <= $limit) return $value;
return mb_substr($value, 0, $limit) . $end;
}

function str_random(int $length = 16): string
{
return bin2hex(random_bytes($length / 2));
}

function money_format(float $amount, string $symbol = '¥'): string
{
return $symbol . number_format($amount, 2);
}

function array_only(array $array, array $keys): array
{
return array_intersect_key($array, array_flip($keys));
}

function array_except(array $array, array $keys): array
{
return array_diff_key($array, array_flip($keys));
}

echo str_limit("这是一段很长的文本内容", 6) . "\n";
echo str_random(16) . "\n";
echo money_format(12345.67) . "\n";
?>

工具类的设计。

```php
class Str
{
public static function limit(string $value, int $limit = 100, string $end = '...'): string
{
if (mb_strlen($value) <= $limit) return $value;
return mb_substr($value, 0, $limit) . $end;
}

public static function random(int $length = 16): string
{
return bin2hex(random_bytes($length / 2));
}

public static function slug(string $title): string
{
$title = preg_replace('/[^\x{4e00}-\x{9fff}a-zA-Z0-9\s]/u', '', $title);
$title = preg_replace('/\s+/', '-', trim($title));
return strtolower($title);
}

public static function contains(string $haystack, string $needle): bool
{
return str_contains($haystack, $needle);
}

public static function studly(string $value): string
{
return str_replace(' ', '', ucwords(str_replace(['-', '_'], ' ', $value)));
}

public static function camel(string $value): string
{
return lcfirst(self::studly($value));
}
}

class Arr
{
public static function only(array $array, array $keys): array
{
return array_intersect_key($array, array_flip($keys));
}

public static function except(array $array, array $keys): array
{
return array_diff_key($array, array_flip($keys));
}

public static function flatten(array $array): array
{
$result = [];
array_walk_recursive($array, function ($value) use (&$result) {
$result[] = $value;
});
return $result;
}

public static function first(array $array, callable $callback = null, mixed $default = null): mixed
{
foreach ($array as $key => $value) {
if ($callback === null || $callback($value, $key)) {
return $value;
}
}
return $default;
}

public static function pluck(array $array, string $value, ?string $key = null): array
{
$results = [];
foreach ($array as $item) {
$itemValue = data_get($item, $value);
if ($key === null) {
$results[] = $itemValue;
} else {
$itemKey = data_get($item, $key);
$results[$itemKey] = $itemValue;
}
}
return $results;
}
}

echo Str::limit("这是一段很长的文本内容", 6) . "\n";
echo Str::random(16) . "\n";
echo Str::slug("Hello World PHP") . "\n";
print_r(Arr::only(['a' => 1, 'b' => 2, 'c' => 3], ['a', 'c']));
?>

使用trait组织工具方法。

```php
trait Macroable
{
protected static array $macros = [];

public static function macro(string $name, callable $macro): void
{
static::$macros[$name] = $macro;
}

public static function __callStatic(string $method, array $parameters): mixed
{
if (isset(static::$macros[$method])) {
return (static::$macros[$method])(...$parameters);
}
throw new BadMethodCallException("方法不存在: $method");
}
}

class StringHelper
{
use Macroable;
}

StringHelper::macro('greet', fn(string $name) => "Hello, $name!");
echo StringHelper::greet('张三') . "\n";
?>

全局函数和工具类的设计没有定论。使用全局函数或静态工具类都可以。关键是保持命名一致性和团队约定。Laravel的Str和Arr类提供了很好的参考。