12/27/2018 7:47:30 PM Hello Friends, I was wondering do I need to refactor this codes that is using a delegate with a lambda expression, or is this best practice? Thanks ! namespace Delagate { delegate bool MeDelagate( int n); class Program { //static bool LessThanFive(int n) { return n // static bool LessThanTen(int n) { return n //static bool GreaterThanThirteen(int n) { return n > 13; } static void Main( string [] args) { int [] numbers = new [] { 2, 7, 3, 7, 9, 17,5, 1, 8, 1700 }; IEnumerable int > result = RunNumbersThroughGauntlet( numbers, n => n > 1500 ); foreach ( int n in result) Console.WriteLine(n); } static IEnumerable int > RunNumbersThroughGauntlet(IEnumerable int > numbers, MeDelagate gauntlet) { foreach ( int number in numbers) if (gauntlet(number)) yield return number; } } }

You can write simple linq query or create delegate and pass to linq query int[] numbers = new[] { 2, 7, 3, 7, 9, 17, 5, 1, 8, 1700 }; Func NumberGreaterThan1500 = n => n > 1500; var result= numbers.Where(n => n > 1500); //var result = numbers.Where(NumberGreaterThan1500); foreach (var num in result) { Console.WriteLine(num); } Console.ReadLine(); Kindly read below to understand Func https://dotnetwithwinowandweb.com/2018/09/02/what-are-action-func-and-predicate-in-c-can-you-give-their-practical-use/

Answers

Delegates and Lambda Expressions

Ronald Rex

584

12/27/2018 7:47:30 PM

Hello Friends,

I was wondering do I need to refactor this codes that is using a delegate with a lambda expression, or is this best practice? Thanks !

namespace Delagate
{
delegate bool MeDelagate(int n);
class Program
{
//static bool LessThanFive(int n) { return n < 5; }
// static bool LessThanTen(int n) { return n < 10; }
//static bool GreaterThanThirteen(int n) { return n > 13; }
static void Main(string[] args)
{
int[] numbers = new[] { 2, 7, 3, 7, 9, 17,5, 1, 8, 1700 };
IEnumerable<int> result = RunNumbersThroughGauntlet(numbers, n => n > 1500);
foreach (int n in result)
Console.WriteLine(n);
}
static IEnumerable<int> RunNumbersThroughGauntlet(IEnumerable<int> numbers, MeDelagate gauntlet)
{
foreach (int number in numbers)
if (gauntlet(number))
yield return number;
}
}
}