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Examples of errors detected by the V308…

Examples of errors detected by the V3083 diagnostic

April 5, 2021

V3083. Unsafe invocation of event, NullReferenceException is possible. Consider assigning event to a local variable before invoking it.


Accord.Net

V3083 Unsafe invocation of event 'TempoDetected', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. Accord.Audio Metronome.cs 223


private void timeUp_Elapsed(object sender, ElapsedEventArgs e)
{
  ....
  if (TempoDetected != null)
    TempoDetected(this, EventArgs.Empty);
}

Old NASA World Wind (C#)

V3083 Unsafe invocation of event 'Elapsed', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. TimeKeeper.cs 78


private static void m_timer_Elapsed(....)
{
  ....
  if (Elapsed != null)
     Elapsed(sender, e);
}

Similar errors can be found in some other places:

  • V3083 Unsafe invocation of event 'Navigate', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. InternalWebBrowser.cs 65
  • V3083 Unsafe invocation of event 'Close', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. InternalWebBrowser.cs 73
  • V3083 Unsafe invocation of event 'OnMouseEnterEvent', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. WavingFlagLayer.cs 672
  • And 22 additional diagnostic messages.

Unity3D

V3083 Unsafe invocation of event 'unload', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. AssetBundleDemo AssetBundleManager.cs 47


internal void OnUnload()
{
  m_AssetBundle.Unload(false);
  if (unload != null)
    unload(); // <=
}

Logify Alert Clients

V3083 Unsafe invocation of event, NullReferenceException is possible. Consider assigning event to a local variable before invoking it. LogifyClient.cs 169


protected override bool
RaiseConfirmationDialogShowing(ReportConfirmationModel model) {
  if(ConfirmationDialogShowing != null) {                   // <=
    ConfirmationDialogModel actualModel =
      model as ConfirmationDialogModel;
    if(actualModel == null)
        return false;
    ConfirmationDialogEventArgs args =
      new ConfirmationDialogEventArgs(actualModel);
    ConfirmationDialogShowing(this, args);                  // <=
    return args.Handled;
  }
  return false;
}

Similar errors can be found in some other places:

  • V3083 Unsafe invocation of event 'NotifyProgress', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. Zip.cs 1035
  • V3083 Unsafe invocation of event, NullReferenceException is possible. Consider assigning event to a local variable before invoking it. LogifyClient.cs 156
  • V3083 Unsafe invocation of event 'FocusChanged', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. BreadcrumbsRecorder.cs 391
  • And 4 additional diagnostic messages.

Infer.NET

V3083 Unsafe invocation of event 'Started', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. Evaluator RecommenderRun.cs 115


public class RecommenderRun
{
  ....
  public event EventHandler Started;
  ....
  public void Execute()
  {
    if (this.Started != null)
    {
      this.Started(this, EventArgs.Empty);
    }
      ....
  }
  ....
}

AWS SDK for .NET

V3083 [CWE-367] Unsafe invocation of event 'mOnSyncSuccess', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. AWSSDK.CognitoSync.PCL Dataset.cs 827


protected void FireSyncSuccessEvent(List<Record> records)
{
  if (mOnSyncSuccess != null)
  {
    mOnSyncSuccess(this, new SyncSuccessEventArgs(records));
  }
}

Similar errors can be found in some other places:

  • V3083 [CWE-367] Unsafe invocation of event 'mOnSyncFailure', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. AWSSDK.CognitoSync.PCL Dataset.cs 839
  • V3083 [CWE-367] Unsafe invocation of event, NullReferenceException is possible. Consider assigning event to a local variable before invoking it. AWSSDK.Core.PCL AmazonServiceClient.cs 332
  • V3083 [CWE-367] Unsafe invocation of event, NullReferenceException is possible. Consider assigning event to a local variable before invoking it. AWSSDK.Core.PCL AmazonServiceClient.cs 344
  • And 7 additional diagnostic messages.

ShareX

V3083 [CWE-367] Unsafe invocation of event 'NewsLoaded', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. NewsListControl.cs 111


protected void OnNewsLoaded()
{
  if (NewsLoaded != null)
  {
    NewsLoaded(this, EventArgs.Empty);
  }
}

Telerik UI for UWP

V3083 Unsafe invocation of event 'Completed', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. ActionBase.cs 32


protected virtual void OnCompleted()
{
  this.IsCompleted = true;

  if (this.Completed != null)
  {
    this.Completed(this, EventArgs.Empty);
  }
}

Azure SDK for .NET

V3083 Unsafe invocation of event '_onChange', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. ClientOptionsMonitor.cs 44


private event Action<TOptions, string> _onChange;
....
private void InvokeChanged(....)
{
  ....
  if (_onChange != null)
  {
    _onChange.Invoke(options, name);
  }
}

osu!

V3083 [CWE-367] Unsafe invocation of event 'ObjectConverted', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. BeatmapConverter.cs 82


private List<T> convertHitObjects(....)
{
  ....
  if (ObjectConverted != null)
  {
    converted = converted.ToList();
    ObjectConverted.Invoke(obj, converted);
  }
  ....
}

Emby

V3083 Unsafe invocation of event 'RefreshStarted', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. ProviderManager.cs 943


public void OnRefreshStart(BaseItem item)
{
  ....

  if (RefreshStarted != null)
  {
    RefreshStarted(this, new GenericEventArgs<BaseItem>(item));
  }
}

RunUO

V3083 Unsafe invocation of event 'ServerStarted', NullReferenceException is possible. Consider assigning event to a local variable before invoking it. EventSink.cs 921


public static void InvokeServerStarted()
{
  if ( ServerStarted != null )
    ServerStarted();
}

ILSpy

V3083 Unsafe invocation of event, NullReferenceException is possible. Consider assigning event to a local variable before invoking it. ILSpy MainWindow.xaml.cs 787class ResXResourceWriter : IDisposable


void assemblyList_Assemblies_CollectionChanged(....)
{
  ....
  if (CurrentAssemblyListChanged != null)
    CurrentAssemblyListChanged(this, e);      // <=
}

void assemblyList_Assemblies_CollectionChanged(....)
{
  ....
  CurrentAssemblyListChanged?.Invoke(this, e);
}

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