PHP -避免编写嵌套的if语句

switch ($condition) {
    case 'condition1':
        // 执行条件1的代码块
        break;
    case 'condition2':
        // 执行条件2的代码块
        break;
    case 'condition3':
        // 执行条件3的代码块
        break;
    default:
        // 默认情况下执行的代码块
        break;
}

$conditions = [
    'condition1' => function() {
        // 执行条件1的代码块
    },
    'condition2' => function() {
        // 执行条件2的代码块
    },
    'condition3' => function() {
        // 执行条件3的代码块
    },
];

if (isset($conditions[$condition])) {
    $conditions[$condition]();
} else {
    // 默认情况下执行的代码块
}

interface Strategy {
    public function execute();
}

class Condition1Strategy implements Strategy {
    public function execute() {
        // 执行条件1的代码块
    }
}

class Condition2Strategy implements Strategy {
    public function execute() {
        // 执行条件2的代码块
    }
}

class Condition3Strategy implements Strategy {
    public function execute() {
        // 执行条件3的代码块
    }
}

$strategies = [
    'condition1' => new Condition1Strategy(),
    'condition2' => new Condition2Strategy(),
    'condition3' => new Condition3Strategy(),
];

if (isset($strategies[$condition])) {
    $strategies[$condition]->execute();
} else {
    // 默认情况下执行的代码块
}