Are there Func objects with more than 4 parameters?
I saw here that Func<(Of <(T1, T2, T3, T4, TResult>)>) D开发者_Go百科elegate
was the last Func
in the namespace. What do you do if you need more than 4 parameters?
You could create your own Func
delegates, or you could wait for .NET 4 to arrive (it includes built-in Func
and Action
delegates with up to sixteen parameters).
As others have mentioned, if you find yourself needing a delegate that takes this many parameters then maybe it's time to think about some sort of refactoring.
public delegate TResult Func<T1, T2, T3, T4, T5, TResult>
(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5);
public delegate TResult Func<T1, T2, T3, T4, T5, T6, TResult>
(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5, T6 arg6);
public delegate TResult Func<T1, T2, T3, T4, T5, T6, T7, TResult>
(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5, T6 arg6, T7 arg7);
public delegate TResult Func<T1, T2, T3, T4, T5, T6, T7, T8, TResult>
(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5, T6 arg6, T7 arg7, T8 arg8);
// etc
In .Net 4, there's overloads till 17 (give or take) parameters.
Personally, I think that's nuts. If you need more than 4 parameters, then it's time to create a new class that has all the parameters you need as properties.
Create a parameter object, perhaps?
The refactor catalog has a good description.
Kindness,
Dan
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