C#: Difference between ' += anEvent' and ' += new EventHandler(anEvent)'

c# delegates event-handling
Andreas Grech picture Andreas Grech · Feb 15, 2009 · Viewed 11.5k times · Source

Take the below code:

private void anEvent(object sender, EventArgs e) {
    //some code
}

What is the difference between the following ?

[object].[event] += anEvent;

//and

[object].[event] += new EventHandler(anEvent);

[UPDATE]

Apparently, there is no difference between the two...the former is just syntactic sugar of the latter.

Answer

driis picture driis · Feb 15, 2009

There is no difference. In your first example, the compiler will automatically infer the delegate you would like to instantiate. In the second example, you explicitly define the delegate.

Delegate inference was added in C# 2.0. So for C# 1.0 projects, second example was your only option. For 2.0 projects, the first example using inference is what I would prefer to use and see in the codebase - since it is more concise.

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