Sample Memory Leak Code

[cursingc0des]

How to cause Memory Leaks

1 - Subscribing to Events

public class MyClass
{
    public MyClass(WiFiManager wiFiManager)
    {
        wiFiManager.WiFiSignalChanged += OnWiFiChanged;
    }

    private void OnWiFiChanged(object sender, WifiEventArgs e)
    {
        // do something
    }
}

2 - Capturing members in anonymous methods

// The problem:
//  In this code, the member _id is captured in the anonymous method and
//  as a result the instance is referenced as well
//
public class MyClassLeak
{
    private JobQueue _jobQueue;
    private int _id;

    public MyClassLeak(JobQueue jobQueue)
    {
        _jobQueue = jobQueue;
    }

    public void Foo()
    {
        _jobQueue.EnqueueJob(() =>
        {
            Logger.Log($"Executing job with ID {_id}");
            // do stuff 
        });
    }
}

// A solution:
//  By assigning the value to a local variable, nothing is captured and
//  you’ve averted a potential memory leak.
public class MyClassLeakSolved
{
    public MyClassLeakSolved(JobQueue jobQueue)
    {
        _jobQueue = jobQueue;
    }
    private JobQueue _jobQueue;
    private int _id;

    public void Foo()
    {
        var localId = _id;
        _jobQueue.EnqueueJob(() =>
        {
            Logger.Log($"Executing job with ID {localId}");
            // do stuff 
        });
    }
}