Equivalent of typedef in C#

Is there a typedef equivalent in C#, or someway to get some sort of similar behaviour? I've done some googling, but everywhere I look seems to be negative. Currently I have a situation similar to the following:

class GenericClass<T> 
{
    public event EventHandler<EventData> MyEvent;
    public class EventData : EventArgs { /* snip */ }
    // ... snip
}

Now, it doesn't take a rocket scientist to figure out that this can very quickly lead to a lot of typing (apologies for the horrible pun) when trying to implement a handler for that event. It'd end up being something like this:

GenericClass<int> gcInt = new GenericClass<int>;
gcInt.MyEvent += new EventHandler<GenericClass<int>.EventData>(gcInt_MyEvent);
// ...

private void gcInt_MyEvent(object sender, GenericClass<int>.EventData e)
{
    throw new NotImplementedException();
}

Except, in my case, I was already using a complex type, not just an int. It'd be nice if it were possible to simplify this a little...

Edit: ie. perhaps typedefing the EventHandler instead of needing to redefine it to get similar behaviour.

---

No, there's no true equivalent of typedef. You can use 'using' directives within one file, eg

using CustomerList = System.Collections.Generic.List<Customer>;

but that will only impact that source file. In C and C++, my experience is that typedef is usually used within .h files which are included widely - so a single typedef can be used over a whole project. That ability does not exist in C#, because there's no #include functionality in C# that would allow you to include the using directives from one file in another.

Fortunately, the example you give does have a fix - implicit method group conversion. You can change your event subscription line to just:

gcInt.MyEvent += gcInt_MyEvent;

:)

---

Jon really gave a nice solution, I didn't know you could do that!

At times what I resorted to was inheriting from the class and creating its constructors. Eg

public class FooList : List<Foo> { ... }

Not the best solution (unless your assembly gets used by other people), but it works.

---

If you know what you're doing, you can define a class with implicit operators to convert between the alias class and the actual class.

class TypedefString // Example with a string "typedef"
{
    private string Value = "";
    public static implicit operator string(TypedefString ts)
    {
        return ((ts == null) ? null : ts.Value);
    }
    public static implicit operator TypedefString(string val)
    {
        return new TypedefString { Value = val };
    }
}

I don't actually endorse this and haven't ever used something like this, but this could probably work for some specific circumstances.

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