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Code Analyzer for C#

There is a newer version: 10.4.0.108396

Why is this an issue?
When raising an event, two arguments are expected by the EventHandler delegate: Sender and event-data. There are three guidelines
regarding these parameters:

   Do not pass null as the sender when raising a non-static event. 
   Do pass null as the sender when raising a static event. 
   Do not pass null as the event-data. If no data should be passed, then EventArgs.Empty should be used. 

This rule raises an issue when any of these guidelines is not met.
Noncompliant code example
using System;

namespace MyLibrary
{
  class Foo
  {
    public event EventHandler ThresholdReached;

    protected virtual void OnThresholdReached(EventArgs e)
    {
        ThresholdReached?.Invoke(null, e); // Noncompliant
    }
  }
}

Compliant solution
using System;

namespace MyLibrary
{
  class Foo
  {
    public event EventHandler ThresholdReached;

    protected virtual void OnThresholdReached(EventArgs e)
    {
        ThresholdReached?.Invoke(this, e);
    }
  }
}