Temukan, perbaiki, dan cegah kebocoran memori di C # .NET: 8 praktik terbaik

Untuk calon siswa kursus "Pengembang C #" dan semua yang tertarik, kami menyiapkan terjemahan materi yang bermanfaat.



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Siapapun yang pernah mengerjakan proyek perusahaan besar tahu bahwa kebocoran memori seperti tikus di hotel besar. Anda mungkin tidak menyadarinya jika jumlahnya sedikit, tetapi Anda harus selalu waspada jika mereka berkembang biak, menyelinap ke dapur dan mengotori segala sesuatu di sekitarnya.

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public class MyClass
{
    private int _wiFiChangesCounter = 0;
 
    public MyClass(WiFiManager wiFiManager)
    {
        wiFiManager.WiFiSignalChanged += (s, e) => _wiFiChangesCounter++;
    }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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public class MyClass
{
    public MyClass(WiFiManager wiFiManager)
    {
        Timer timer = new Timer(HandleTick);
        timer.Change(TimeSpan.FromSeconds(5), TimeSpan.FromSeconds(5));
    }
 
    private void HandleTick(object state)
    {
        // do something
    }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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    private IntPtr _bufferPtr;
    public int BUFFER_SIZE = 1024 * 1024; // 1 MB
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    {
        _bufferPtr =  Marshal.AllocHGlobal(BUFFER_SIZE);
    }
 
    protected virtual void Dispose(bool disposing)
    {
        if (_disposed)
            return;
 
        if (disposing)
        {
            // Free any other managed objects here.
        }
 
        // Free any unmanaged objects here.
        Marshal.FreeHGlobal(_bufferPtr);
        _disposed = true;
    }
 
    public void Dispose()
    {
        Dispose(true);
        GC.SuppressFinalize(this);
    }
 
    ~MyClass()
    {
        Dispose(false);
    }
}

      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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PerformanceCounter ctr1 = new PerformanceCounter("Process", "Private Bytes", Process.GetCurrentProcess().ProcessName);
PerformanceCounter ctr2 = new PerformanceCounter(".NET CLR Memory", "# Gen 0 Collections", Process.GetCurrentProcess().ProcessName);
PerformanceCounter ctr3 = new PerformanceCounter(".NET CLR Memory", "# Gen 1 Collections", Process.GetCurrentProcess().ProcessName);
PerformanceCounter ctr4 = new PerformanceCounter(".NET CLR Memory", "# Gen 2 Collections", Process.GetCurrentProcess().ProcessName);
PerformanceCounter ctr5 = new PerformanceCounter(".NET CLR Memory", "Gen 0 heap size", Process.GetCurrentProcess().ProcessName);
//...
Debug.WriteLine("ctr1 = " + ctr1 .NextValue());
Debug.WriteLine("ctr2 = " + ctr2 .NextValue());
Debug.WriteLine("ctr3 = " + ctr3 .NextValue());
Debug.WriteLine("ctr4 = " + ctr4 .NextValue());
Debug.WriteLine("ctr5 = " + ctr5 .NextValue());
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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[Test]
void MemoryLeakTest()
{
  var weakRef = new WeakReference(leakyObject)
  // Ryn an operation with leakyObject
  GC.Collect();
  GC.WaitForPendingFinalizers();
  GC.Collect();
  Assert.IsFalse(weakRef.IsAlive);
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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MemAssertion.NoInstances(typeof(MyLeakyClass));
MemAssertion.NoNewInstances(typeof(MyLeakyClass), lastSnapshot);
MemAssertion.MaxNewInstances(typeof(Bitmap), 10);
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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