Delegates What are they?

Question

Hi I'm kind of new to this as I'm a student. Probably this question is very basic for most of you but here we go. I've been reading about delagates today and what I understand about them is the following: 1- Delegates can access methods at run time. 2- Delegates are similar to interfaces but not quite. Now if some of you could explain to me in simple words how a delegates access methods at run time and why this is an advantage for a developer I'd be very grateful. NOTE: I've been reading the book for the exam 70-315 and it is just very hard to understand. Thanks a lot Eduardo

Pathum Fernando · Answer

Delegates is a type that reference Method. When it assigned by a method it behaves exactly same as that method. It can be used as parameters and can be returned a value. So it has same what are the methods have. For more Read this article http://www.pathumf.blogspot.com/2011/11/delegates-in-c.html

Eduardo Arias · Answer

Thank you for your time. This is very interesting. So the delagate would be a kind of middle man between the two methods you are talking about ... is this correct? So in the example you are giving me Couldn't I just use a method with if-else or a switch statement to identify the iformation coming from the port to let's say a GetScannerInformation() for example? Thanks you Eduardo

Satyapriya Nayak · Answer

Normal 0 Hi Eduardo Delegates : - It is a procedure pointer which stores the memory address of another procedure. Ex:- using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace WindowsFormsApplication1 { public partial class Form1 : Form { public delegate void abhisek(int x int y); public Form1() { InitializeComponent(); } private void button1_Click(object sender EventArgs e) { abhisek a = null; a = rajiv; a.Invoke(10 20); } public void rajiv(int x int y) { int z = 0; z = x + y; MessageBox.Show(z.ToString()); } } } Thanks

Ryan Alford · Answer

probably the most basic use of Delegates is for updating a form using a background process. so that you have a serial port open waiting for a barcode scanner to scan something. when something is scanned it will fire the receiveData event for the serial port. however you would not be able to update the form with the data from the scan because they were started in different threads. so you would use a delegate. the delegate would delegate between the main thread and another thread allowing you to set .Text properties on the form. that's my interpretation from using them.

Delegates, What are they?