MVC Pattern

MVC Pattern stands for Model-View-Controller Pattern. This pattern is used to separate application's concerns.

• Model - Model represents an object or JAVA POJO carrying data. It can also have logic to update controller if its data changes.

• View - View represents the visualization of the data that model contains.

• Controller - Controller acts on both model and view. It controls the data flow into model object and updates the view whenever data changes. It keeps view and model separate.

Implementation

We are going to create a Student object acting as a model.StudentView will be a view class which can print student details on console and StudentController is the controller class responsible to store data in Student object and update view StudentView accordingly.

 

Step 1

Create Model.

Student.cs

public class Student {
   private String rollNo;
   private String name;
   
   public String getRollNo() {
      return rollNo;
   }
   
   public void setRollNo(String rollNo) {
      this.rollNo = rollNo;
   }
   
   public String getName() {
      return name;
   }
   
   public void setName(String name) {
      this.name = name;
   }
}

Step 2

Create View.

StudentView.cs

public class StudentView {
   public void printStudentDetails(String studentName, String studentRollNo){
      Console.WriteLine("Student: ");
      Console.WriteLine("Name: " + studentName);
      Console.WriteLine("Roll No: " + studentRollNo);
   }
}

Step 3

Create Controller.

StudentController.cs

public class StudentController {
   private Student model;
   private StudentView view;

   public StudentController(Student model, StudentView view){
      this.model = model;
      this.view = view;
   }

   public void setStudentName(String name){
      model.setName(name);		
   }

   public String getStudentName(){
      return model.getName();		
   }

   public void setStudentRollNo(String rollNo){
      model.setRollNo(rollNo);		
   }

   public String getStudentRollNo(){
      return model.getRollNo();		
   }

   public void updateView(){				
      view.printStudentDetails(model.getName(), model.getRollNo());
   }	
}

Step 4

Use the StudentController methods to demonstrate MVC design pattern usage.

MVCPatternDemo.cs

public class MVCPatternDemo {
   public static void main(String[] args) {

      //fetch student record based on his roll no from the database
      Student model  = retriveStudentFromDatabase();

      //Create a view : to write student details on console
      StudentView view = new StudentView();

      StudentController controller = new StudentController(model, view);

      controller.updateView();

      //update model data
      controller.setStudentName("John");

      controller.updateView();
   }

   private static Student retriveStudentFromDatabase(){
      Student student = new Student();
      student.setName("Robert");
      student.setRollNo("10");
      return student;
   }
}

Ping IP Addresses

Small module written to replicate the ping functionality in C# code

	public bool Ping (string host, int attempts, int timeout)
	{
	System.Net.NetworkInformation.Ping ping =
	new System.Net.NetworkInformation.Ping ();
	System.Net.NetworkInformation.PingReply pingReply;
	for (int i = 0; i < attempts; i++)
	{
	try
	{
	pingReply = ping.Send (host, timeout);
	// If there is a successful ping then return true.
	if (pingReply != null &&
	pingReply.Status == System.Net.NetworkInformation.IPStatus.Success)
	return true;
	}
	catch
	{
	// Do nothing and let it try again until the attempts are exausted.
	// Exceptions are thrown for normal ping failurs like address lookup
	// failed. For this reason we are supressing errors.
	}
	}
	// Return false if we can't successfully ping the server after several attempts.
	return false;
	}

view raw Ping.cs hosted with ❤ by GitHub