private static void DelegatePresentation()
{
var a = 3;
var b = 2;
IntOperation operation = new IntOperation(SomeFunction);
//operation = SomeFunction; //or this
//operation = Math.Min; // or this
var ret = operation.Invoke(a, b);
//var ret2 = operation(a, b); //shorter version
Console.WriteLine("Sum on {0} and {1} is {2}", a, b, ret);
operation = Math.Max;
ret = operation.Invoke(a, b); //subtraction
Console.WriteLine("Max on {0} and {1} is {2}", a, b, ret);
Func <int, int, int> func = SomeFunction; //new SomeFunction<int, int, int>(operation);
Action <string> action = Print;
_action = action;
action("Text");
//subscribing to delegate - works only with void delegates
action += s => { Console.WriteLine("1"); };
action += s => { Console.WriteLine("s2"); };
action("");
ExecuteDelegate(operation);
}
static void Main()
{
var a = 3;
var b = 2;
var operation = new IntOperation((x, y) => { return(x - y); });
//operation = new IntOperation((x, y) => x - y);
//operation = (x, y) => x - y;
var ret = operation.Invoke(a, b); //sum
Console.WriteLine("Sum on {0} and {1} is {2}", a, b, ret);
operation = (x, y) => { Console.WriteLine("sub"); return(x - y); };
ret = operation.Invoke(a, b); //subtraction
Console.WriteLine("Subtraction on {0} and {1} is {2}", a, b, ret);
operation = (x, y) => { Console.WriteLine("prod"); return(x * y); }; //what about += events
ret = operation.Invoke(a, b); //product
Console.WriteLine("Product on {0} and {1} is {2}", a, b, ret);
Func <int, int, int> func = (x, y) => 3;
func = (x, y) => x * y;
func = (x, y) =>
{
Console.WriteLine("Dividing integers is not very convenient. Think of using doubles or decimals");
var result = x / (double)y;
return((int)result);
};
Action <int, int> actionGeneric = ((x, y) =>
{
Console.WriteLine(ret);
Console.WriteLine(operation(x, y));
});
Action emptyAction = () => { };
emptyAction(); // does nothing
Console.ReadKey();
}