Posts Tagged ‘lamdba’

Function within a method in C# / csharp / dotnet

Mar 5th, 2012

I have since the birth of dotnet missed the possibility to have a function inside a function like one can in Pascal.

With lambda, and possibly Dotnet4(?) it is possible.  Below is a rather stupid example.

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internal int AddMaxWierd( int x, int y )
{
Func Max = delegate( int a ){
return Math.Min( a, 10 );
};

return Max(x) + Max(y);
}

If the inner method doesn’t have a return value, use “Action” instead of “Func”.
See how there is only one Manipulate method in the class, the other Manipulate method is hidden within the method.

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internal void Manipulate( CustomerList Customer customers )
{
Action<Customer> Manipulate = delegate( Customer customer )
{
// do stuff...
};

foreach( var customer in customers ){
Manipulate( customer );
}

}

 

Update:

In C#7 it can be done. https://github.com/dotnet/roslyn/issues/6505