Csharp/CSharp Tutorial/Class/ToString

Demonstrate ToString()

<source lang="csharp">using System;

class MyClass {

 static int count = 0; 
 int id; 

 public MyClass() { 
   id = count; 
   count++; 
 } 

 public override string ToString() { 
   return "MyClass object #" + id; 
 } 

}

class MainClass {

 public static void Main() { 
   MyClass ob1 = new MyClass(); 
   MyClass ob2 = new MyClass(); 
   MyClass ob3 = new MyClass(); 

   Console.WriteLine(ob1); 
   Console.WriteLine(ob2); 
   Console.WriteLine(ob3); 

 } 

}</source>

MyClass object #0
MyClass object #1
MyClass object #2

How to override the ToString() method

<source lang="csharp">using System; public class Employee {

 public string firstName;
 public string lastName;
 public Employee(string firstName, string lastName)
 {
   this.firstName = firstName;
   this.lastName = lastName;
 }
 public override string ToString()
 {
   return firstName + " " + lastName;
 }

} class MainClass {

 public static void Main()
 {
   Employee myEmployee = new Employee("A", "M");
   Employee myOtherEmployee = new Employee("B", "N");
   Console.WriteLine("myEmployee.ToString() = " + myEmployee.ToString());
   Console.WriteLine("myOtherEmployee.ToString() = " + myOtherEmployee.ToString());
 }

}</source>

myEmployee.ToString() = A M
myOtherEmployee.ToString() = B N

mark override when overriding ToString

<source lang="csharp">using System; public class Thing {

   public int i = 2;
   public int j = 3;
   override public string ToString() {
       return String.Format("i = {0}, j = {1}", i, j);
   }

}</source>

override ToString

<source lang="csharp">using System; using System.Collections;

struct RGB {

   public int red;
   public int green;
   public int blue;
  
   public RGB(int red, int green, int blue)
   {
       this.red = red;
       this.green = green;
       this.blue = blue;
   }
  
   public override String ToString()
   {
       return red.ToString("X") 
           + green.ToString("X") 
           + blue.ToString("X");
   }

}

class BoxTest {

   static ArrayList rgbValues;
  
   public static void Main()
   {
       RGB rgb = new RGB(255, 255, 255);
  
       rgbValues = new ArrayList();
       rgbValues.Add(rgb);
  
       Console.WriteLine("The RGB value is {0}", rgb);
   }

}</source>