The design patterns are the recurring solution to recurring problem in Software architecture.
OR
Design pattern are the time tested practices for OOP problem. It is the process of solving object oriented programming language in much better ways.
There are 3 basic classification o design pattern
1. Creational patterns
2. Structural Patterns
3. Behavioral Pattern
Now let see some example of Creational Patterns example
1. Singleton Pattern
2. Abstract Factory Pattern
3. Factory Method pattern
4. Prototype Pattern
5. Builder Pattern
Singleton Pattern:
In this design pattern, we can create only one instance of Class. That instance needs to be accessible in different part of application. It can be use as global.
For example, we can use this pattern in so many scenarios like logging, Database access, and Holding Database Connection instance etc.
This pattern can be achieved by
1. Creating private construct of class.
2. Creating Instances and Method as static.
Now create the class like given below
namespace WebApplication2 { public class SingleTonTest { public static int intCounter; private SingleTonTest() { } public static void Hit() { intCounter++; } public static int getTotalHits() { return intCounter; } } }
Step 2 Write the code in UI Layer like this
using System; namespace WebApplication2 { public partial class WebForm1 : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { } protected void Button1_Click(object sender, EventArgs e) { HiCounter(); } private void HiCounter() { SingleTonTest.Hit(); Label1.Text = SingleTonTest.getTotalHits().ToString(); } protected void Button2_Click(object sender, EventArgs e) { HiCounter(); } } }
Summary:
Here we learnt that how to use singleton design pattern in C#.