Question

What is the difference between:

this.btnConnect.Click += btnConnect_Click;

and:

this.btnConnect.Click += new RoutedEventHandler(btnConnect_Click);

It seems to work the same either way, but Visual Studio IntelliSense inserts the second example and I’m curious why.

My initial guess is that using the IntelliSense version makes it so that each button calls its own instance of the RoutedEventHandler, making it thread-safe?
And that using the first example, then each button would call the same instance of that method and they might step on each others feet.

Answer 1

It is the same thing, the first is just a syntactic sugar, i.e. compiler generates the same IL bytecode for both – there is always a delegate instance created.

IIRC, the first version of C# didn’t allow the first syntax, it was introduced in C# 2.0.