internal void EnemyKilled(object sender, Enemy.EnemyKilledEventArgs e)
 {
     enemyAliveCount--;
     EarnMoney(e.enemy);
     xEnemyAliveCount.text = "剩余敌人数量    " + enemyAliveCount + " / " + waves[currentWave - 1].Count;
 }
 internal void EnemyKilled(object sender, Enemy.EnemyKilledEventArgs e)
 {
     EarnExp(e.enemy);
 }