function Return

In this chapter you will learn:

How to return value from a function
How to return an object value from a method
How to return a value of an array from a method

Return value from a function

Methods return a value to the calling routine using this form of return:

return value;

value is the value returned.

using System;/*j  a  v a  2 s .  co m*/

class MainClass
{
   public static int GetHour()
   {
      return 123;                   
   }

   static void Main()
   {
      Console.WriteLine("Hour: {0}", GetHour());
   }
}

The code above generates the following result.

Return an object

The following code defines a method and return its instance from a method.

using System; //  j  av  a  2s . c o m
 
class Rect { 
  int width; 
  int height; 
 
  public Rect(int w, int h) { 
    width = w; 
    height = h; 
  } 
 
  public int area() { 
    return width * height; 
  } 
 
  public void show() { 
    Console.WriteLine(width + " " + height); 
  } 
 
  public Rect enlarge(int factor) { 
    return new Rect(width * factor, height * factor); 
  } 
} 
  
class MainClass { 
  public static void Main() {   
    Rect r1 = new Rect(4, 5); 
 
    Console.Write("Dimensions of r1: "); 
    r1.show(); 
    Console.WriteLine("Area of r1: " + r1.area()); 
 
    Console.WriteLine(); 
 
    // create a rectangle that is twice as big as r1 
    Rect r2 = r1.enlarge(2); 
 
    Console.Write("Dimensions of r2: "); 
    r2.show(); 
    Console.WriteLine("Area of r2 " + r2.area()); 
  } 
}

The code above generates the following result.

Return an array

The following code defines a method returning array.

using System; // j a v a 2s .  c  om
 
class Factor { 
  public int[] findfactors(int num, out int numfactors) { 
    int[] facts = new int[80]; 
    int i, j; 
 
    for(i=2, j=0; i < num/2 + 1; i++)  
      if( (num%i)==0 ) { 
        facts[j] = i; 
        j++; 
      } 
     
    numfactors = j; 
    return facts; 
  } 
} 
  
class MainClass { 
  public static void Main() {   
    Factor f = new Factor(); 
    int numfactors; 
    int[] factors; 
 
    factors = f.findfactors(1000, out numfactors); 
 
    Console.WriteLine("Factors for 1000 are: "); 
    for(int i=0; i < numfactors; i++) 
      Console.Write(factors[i] + " "); 
       
    Console.WriteLine();    
  } 
}