Generic Methods as Casts

re: Generic Methods as Casts

Tom Kirby-Green — Thu, 07 Jun 2007 23:31:12 GMT

Hi Krzysztof,

Do you and Brad plan to write an updated edition of the Framework Class Guidelines? I was wondering if you chaps planned covering designing types for more declarative APIs (i.e. XAML bindings), designing types to enable rich and efficient LINQ to Object queries and maybe designing types to support a more functional style of programming.

Or maybe none of these but something different. Do you envisage a new edition of the book any time?

Kind regards,

tom

re: Generic Methods as Casts

IDisposable — Fri, 08 Jun 2007 03:58:03 GMT

Another nice feature of doing it with a generic is that sometimes the type can be inferred. My personal favorite example is:

public object GetValue(string key, object defaultValue)

{

if (this.Values.Contains(key))

return this.Values[key];

else

return defaultValue;

}

// call like this...

int x = (int)configuration.GetValue("X", 0);

Can turn into:

public T GetValue<T>(string key, T defaultValue)

{

if (this.Values.Contains(key))

return (T)this.Values[key];

else

return defaultValue;

}

// call like this...

int x = configuration.GetValue<int>("X", 0);

// or even cooler, like this...

double z = configuration.GetValue("Z", 0.0);

That's the cool bit...

re: Generic Methods as Casts

kcwalina — Mon, 11 Jun 2007 23:27:54 GMT

Tom, we are thinking about updating the guidelines with C# 3.0 and Framework 2.0+ things. We just don't yet have concrete plans. I am starting to draft guidelines (as we speak) and I will post them to the blog. At some point, I will try to fold them into the book.