Suchen, beheben und verhindern Sie Speicherlecks in C # .NET: 8 Best Practices

Für zukünftige Studenten des "C # Developer" -Kurses und alle Interessierten haben wir eine Übersetzung von nützlichem Material vorbereitet.



Wir laden Sie außerdem ein, an dem offenen Webinar zum Thema "LINQ-Methoden, die alles für Sie tun" teilzunehmen. Dort diskutieren die Teilnehmer sechs Vertreter der LINQ-Technologiefamilie, drei Komponenten der Hauptabfrageoperation, verzögerte und sofortige Ausführung sowie parallele Abfragen.

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Jeder, der an einem großen Unternehmensprojekt gearbeitet hat, weiß, dass Speicherlecks wie Ratten in einem großen Hotel sind. Sie werden sie vielleicht nicht bemerken, wenn es nur wenige gibt, aber Sie sollten immer auf der Hut sein, falls sie sich vermehren, sich in die Küche schleichen und alles verschmutzen.

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

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, .NET Memory Profiler SciTech dotMemory, API:

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

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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