C# – What Does the Operator ‘=>’ Mean?

c++delegateslambda

What does the '=>' in this statement signify?

del = new SomeDelegate(() => SomeAction());

Is the above declaration the same as this one?

del = new SomeDelegate(this.SomeAction);

Thanks.

Best Answer

Basically it's specifying an anonymous function, that takes no parameters that calls SomeAction. So yes, they are functionally equivalent. Though not equal. Using the lambda is more equivalent to:

del = new SomeDelegate(this.CallSomeAction);

where CallSomeAction is defined as:

public void CallSomeAction()
{
    this.SomeAction();
}

Hope that helps!

Related Solutions

C# Syntax – What Does ‘() =>’ Mean?

It's a lambda expression that takes 0 arguments

http://msdn.microsoft.com/en-us/library/bb397687.aspx

C# Lambda Expressions – What Does ‘=>’ Mean?

In C# the lambda operator is written "=>" (usually pronounced "goes to" when read aloud). It means that the arguments on the left are passed into the code block (lambda function / anonymous delegate) on the right.

So if you have a Func or Action (or any of their cousins with more type parameters) then you can assign a lambda expression to them rather than needing to instantiate a delegate or have a separate method for the deferred processing:

//creates a Func that can be called later
Func<int,bool> f = i => i <= 10;
//calls the function with 12 substituted as the parameter
bool ret = f(12);

Best Answer

Related Solutions

C# Syntax – What Does ‘() =>’ Mean?

C# Lambda Expressions – What Does ‘=>’ Mean?

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