Func, Action and lambda
In this chapter you will learn:
Description
lambda expression are often used with
Func and Action delegates.
Func and Action are
predefined delegates with generic parameters.
delegate TResult Func <out TResult> ();
delegate TResult Func <in T, out TResult> (T arg);
delegate TResult Func <in T1, in T2, out TResult> (T1 arg1, T2 arg2);
// www . ja v a2s . c om
... and so on, up to T16
delegate void Action ();
delegate void Action <in T> (T arg);
delegate void Action <in T1, in T2> (T1 arg1, T2 arg2);
... and so on, up to T16
Example
Here is an example of how use to use Func
to create a lambda expression.
using System;//from w ww . j av a2 s . c o m
class Program
{
public static void Main()
{
Func<int, int> sqr = x => x * x;
Console.WriteLine(sqr(3));
}
}
The output:
Next chapter...
What you will learn in the next chapter:
- What are Lambda Capturing Outer Variables
- Example for Lambda Capturing Outer Variables
- Captured variables evaluation
- Update captured variables
- Lifetime of Captured variables