根据用例，我通常会使用一些简单的实现代码，如下面的代码：

abstract class DaysOfWeek

{

const Sunday = 0;

const Monday = 1;

// etc.

}

$today = DaysOfWeek::Sunday;

然而，其他用例可能需要对常量和值进行更多的验证。下面是一个扩展的示例，可以更好地服务于更广泛的情况。

abstract class BasicEnum {

private static $constCacheArray = NULL;

private static function getConstants() {

if (self::$constCacheArray == NULL) {

self::$constCacheArray = [];

}

$calledClass = get_called_class();

if (!array_key_exists($calledClass, self::$constCacheArray)) {

$reflect = new ReflectionClass($calledClass);

self::$constCacheArray[$calledClass] = $reflect->getConstants();

}

return self::$constCacheArray[$calledClass];

}

public static function isValidName($name, $strict = false) {

$constants = self::getConstants();

if ($strict) {

return array_key_exists($name, $constants);

}

$keys = array_map('strtolower', array_keys($constants));

return in_array(strtolower($name), $keys);

}

public static function isValidValue($value, $strict = true) {

$values = array_values(self::getConstants());

return in_array($value, $values, $strict);

}

}

通过创建一个扩展BasicEnum的简单enum类，您现在可以使用方法来进行简单的输入验证:

abstract class DaysOfWeek extends BasicEnum {

const Sunday = 0;

const Monday = 1;

const Tuesday = 2;

const Wednesday = 3;

const Thursday = 4;

const Friday = 5;

const Saturday = 6;

}

DaysOfWeek::isValidName('Humpday'); // false

DaysOfWeek::isValidName('Monday'); // true

DaysOfWeek::isValidName('monday'); // true

DaysOfWeek::isValidName('monday', $strict = true); // false

DaysOfWeek::isValidName(0); // false

DaysOfWeek::isValidValue(0); // true

DaysOfWeek::isValidValue(5); // true

DaysOfWeek::isValidValue(7); // false

DaysOfWeek::isValidValue('Friday'); // false

原创文章，作者：犀牛前端部落，如若转载，请注明出处：https://www.pipipi.net/4493.html