// 示例：用using語句釋放文件流資源  
using (FileStream fileStream = new FileStream("test.txt", FileMode.Open))  
{ 
    byte[] buffer = new byte[1024];  
    int bytesRead = fileStream.Read(buffer, 0, buffer.Length);  
    Console.WriteLine($"讀取了 {bytesRead} 字節(jié)");  
} // 離開using塊，fileStream自動(dòng)調(diào)用Dispose()  

// 示例：WPF窗口關(guān)閉時(shí)取消事件訂閱  
public class MyWindow : Window  
{ 
    public MyWindow()  
    { 
        // 訂閱事件  
        SomeService.OnDataReceived += HandleDataReceived;  
    }  

    private void HandleDataReceived(object sender, EventArgs e)  
    { 
        // 處理數(shù)據(jù)  
    }  

    protected override void OnClosed(EventArgs e)  
    { 
        // 取消訂閱  
        SomeService.OnDataReceived -= HandleDataReceived;  
        base.OnClosed(e);  
    }  
}  

// 示例：用ConcurrentDictionary并設(shè)置最大容量  
public class CacheManager  
{ 
    private static ConcurrentDictionary<int, string> _cache = new ConcurrentDictionary<int, string>();  
    private const int MaxCapacity = 1000;  

    public static void Add(int key, string value)  
    { 
        _cache.TryAdd(key, value);  

        // 如果超過容量，移除最舊的項(xiàng)  
        if (_cache.Count > MaxCapacity)  
        { 
            var oldestKey = _cache.Keys.OrderBy(k => k).First();  
            _cache.TryRemove(oldestKey, out _);  
        }  
    }  
}  

// 故意制造內(nèi)存泄漏（示例）  
public class MemoryLeakExample  
{ 
    private static List<byte[]> _leakList = new List<byte[]>();  

    public void LeakMemory()  
    { 
        for (int i = 0; i < 100000; i++)  
        { 
            _leakList.Add(new byte[1024 * 1024]); // 每次分配1MB內(nèi)存  
        }  
    }  
}  

// 示例：自定義字符串對象池  
public class StringObjectPool : ObjectPool<string>  
{ 
    public StringObjectPool(int maxSize) : base(() => "default", maxSize) {}  
}  

// 使用對象池  
var pool = new StringObjectPool(100);  
string str = pool.Get();  
// 使用完畢后歸還  
pool.Return(str);