Csharp/C Sharp/Data Types/int

Assign value to int variable

 
using System;
class UnaryOpsApp
{
    static void Main(string[] args)
    {
        int a;
        a = -42;
        Console.WriteLine("{0}", a);
    }
}

Assing value to int value

public class Values{
    static void Main( ) {
       int myInt = 7;
       System.Console.WriteLine("Initialized, myInt: {0}", myInt);
       myInt = 5;
       System.Console.WriteLine("After assignment, myInt: {0}",myInt);
    }
 }

Calculate: int and double

/*
C# Programming Tips & Techniques
by Charles Wright, Kris Jamsa
Publisher: Osborne/McGraw-Hill (December 28, 2001)
ISBN: 0072193794
*/
namespace nsArea
{
    using System;
    public class Area
    {
        static public void Main ()
        {
            double Area;
            int Radius = 42;
            GetArea (Radius, out Area);
            Console.WriteLine ("The area of a circle with radius {0} is {1}",
                                Radius, Area);
        }
        static void GetArea (int radius, out double area)
        {
            const double pi = 3.14159;
            area = pi * radius * radius;
        }
    }
}

Calculating the product of three integers.

using System;
public class Product {
    public static void Main(string[] args) {
        int x;
        int y;
        int z;
        int result;
        Console.Write("Enter first integer: ");
        x = Convert.ToInt32(Console.ReadLine());
        Console.Write("Enter second integer: ");
        y = Convert.ToInt32(Console.ReadLine());
        Console.Write("Enter third integer: ");
        z = Convert.ToInt32(Console.ReadLine());
        result = x * y * z;
        Console.WriteLine("Product is {0}", result);
    }
}

Call methods from primitive data types

 
using System;
using System.Collections.Generic;
using System.Text;
class Program {
    static void Main(string[] args) {
        Console.WriteLine(12.GetHashCode());
        Console.WriteLine(12.Equals(23));
        Console.WriteLine(12.GetType().BaseType);
        Console.WriteLine(12.ToString());
        Console.WriteLine(12); // ToString() called automatically.
    }
}

Catch OverflowException Exception

using System;
   
class MainClass
{
    public static void Main()
    {
        try
        {
            checked
            {
                int Integer1;
                int Integer2;
                int Sum;
   
                Integer1 = 9999999999;
                Integer2 = 2000000000;
                Sum = Integer1 + Integer2;
            }
        }
        catch(OverflowException)
        {
            Console.WriteLine("A mathematical operation caused an overflow.");
        }
    }
}

Comparing integers using if statements, equality operators, and relational operators.

       
using System;
public class Comparison
{
   public static void Main( string[] args )
   {
      int number1; 
      int number2; 
      Console.Write( "Enter first integer: " );
      number1 = Convert.ToInt32( Console.ReadLine() );
      Console.Write( "Enter second integer: " );
      number2 = Convert.ToInt32( Console.ReadLine() );
      if ( number1 == number2 )
         Console.WriteLine( "{0} == {1}", number1, number2 );
      if ( number1 != number2 )
         Console.WriteLine( "{0} != {1}", number1, number2 );
      if ( number1 < number2 )
         Console.WriteLine( "{0} < {1}", number1, number2 );
      if ( number1 > number2 )
         Console.WriteLine( "{0} > {1}", number1, number2 );
      if ( number1 <= number2 )
         Console.WriteLine( "{0} <= {1}", number1, number2 );
      if ( number1 >= number2 )
         Console.WriteLine( "{0} >= {1}", number1, number2 );
   } 
}

Convert string value to integer by using the int.TryParse

using System;
public class MainClass {
    public static void Main() {
        int i;
        bool failure = int.TryParse("qwerty", out i);
        bool success = int.TryParse("123", out i);
    }
}

demonstrates variables

using System; 
 
public class Example2DemonstratesVariables {   
  public static void Main() {   
    int x; 
    int y; 
  
    x = 10;
  
    Console.WriteLine("x contains " + x);   
    y = x / 2;  
  
    Console.Write("y contains x / 2: ");  
    Console.WriteLine(y);  
  }   
}

displays a conversion table of Fahrenheit to Celsius

/*  
   This program displays a conversion  
   table of Fahrenheit to Celsius. 
 
   Call this program FtoCTable.cs. 
*/  
 
using System; 
 
public class FtoCTable {  
  public static void Main() {  
    double f, c; 
    int counter; 
 
    counter = 0; 
    for(f = 0.0; f < 100.0; f++) { 
      c = 5.0 / 9.0 * (f - 32.0); // convert to Celsius 
      Console.WriteLine(f + " degrees Fahrenheit is " + 
                        c + " degrees Celsius."); 
 
      counter++; 
 
      // every 10th line, print a blank line        
      if(counter == 10) { 
        Console.WriteLine(); 
        counter = 0; // reset the line counter 
      } 
    } 
  }  
}

Do calculation with int variable

 
using System;
public class MainClass {
    static void Main(string[] args) {
        int a;
        a = -42;
        Console.WriteLine("{0}", a);
        int b = 2;
        int c = 42;
        a = b * -c;
        Console.WriteLine("{0}", a);
    }
}

Format int in Console.WriteLine

 
using System;
public class TestConsoleApp
{
    public static void Main(string[] args)
    {
        Console.WriteLine(123);
        Console.WriteLine("{0}", 123);
        Console.WriteLine("{0:D3}", 123);
    }
}

int array property

 
using System;
public class SomeClass
{
    private int[] nums;
    public SomeClass(int i)
    {
        nums = new int[10];
        nums[0] = i;
    }
    public int[] Nums
    {
        get { return nums; }
        set { nums = value; }
    }
}
   
public class MainClass
{
    public static void Main(string[] args)
    {
        SomeClass sc = new SomeClass(42);
        Console.WriteLine("{0}", sc.Nums[0]);
   
        sc.Nums[0] = sc.Nums[0] + 5;
        Console.WriteLine("{0}", sc.Nums[0]);
    }
}

int based Fahrenheit and Celsius (Centigrade) Scales

 
using System;
public class Class1 {
    public static void Main(string[] args) {
        int nFahr = 100;
        int nBaseFahr;
        nBaseFahr = nFahr - 32;
        int nCelsius;
        nCelsius = (nBaseFahr * 100) / (212 - 32);
        Console.WriteLine(nCelsius);
    }
}

Integer OverFlow

 
using System;
   
class IntegerOverFlow
{
    static void Main(string[] args)
    {
        short s = 32767;
        s++;
        Console.WriteLine(s);
   
        ushort us = 0;
        us--;
        Console.WriteLine(us);
    }
}

Parse int value

 
using System; 
public class Sum { 
  static void Main(String[] args) { 
    int sum = 0; 
    for (int i=0; i<args.Length; i++) 
      sum += int.Parse(args[i]); 
    Console.WriteLine("The sum is " + sum); 
  } 
}

Size of int, double, char and bool

/*
C# Programming Tips & Techniques
by Charles Wright, Kris Jamsa
Publisher: Osborne/McGraw-Hill (December 28, 2001)
ISBN: 0072193794
*/
//
//  Sizes.cs -- returns the sixes of C# data types.
//              Compile with the following command line:
//                  csc /unsafe sizes.cs
//
namespace nsSizes
{
    using System;
    struct TestStruct
    {
        int    x;
        double y;
        char   ch;
    }
    public class Sizes
    {
        static public unsafe void Main ()
        {
            Console.WriteLine ("The size of a bool is " + sizeof (bool));
            Console.WriteLine ("The size of a char is " + sizeof (char));
            Console.WriteLine ("The size of an int is " + sizeof (int));
            Console.WriteLine ("The size of a long is " + sizeof (long));
            Console.WriteLine ("The size of an double is " + sizeof (double));
            Console.WriteLine ("The size TestStruct is " + sizeof (TestStruct));
        }
    }
}

Some Operator on int

using System;
public class MyMainClass10 {
  static void Main(string[] args)  {
    int   a,b,c,d,e,f;
    a = 1;
    b = a + 6;
    c = b - 3;
    d = c * 2;
    e = d / 2;
    f = e % 2;
  }
}

The precision specifier controls the number of significant digits or zeros to the right of a decimal:

 
using System;
public class FormatSpecApp {
    public static void Main(string[] args) {
        int i = 123456;
        
        Console.WriteLine("{0:C5}", i);
        Console.WriteLine("{0:D5}", i);
        Console.WriteLine("{0:E5}", i);
        Console.WriteLine("{0:F5}", i);
        Console.WriteLine("{0:G5}", i);
        Console.WriteLine("{0:N5}", i);
        Console.WriteLine("{0:P5}", i);
        Console.WriteLine("{0:X5}", i);
    }
}

Use #, % and <zero> in int format

 
using System;
public class FormatSpecApp {
    public static void Main(string[] args) {
        int i = 123456;
        Console.WriteLine();
        Console.WriteLine("{0:#0}", i);             // 123456
        Console.WriteLine("{0:#0;(#0)}", i);        // 123456
        Console.WriteLine("{0:#0;(#0);<zero>}", i); // 123456
        Console.WriteLine("{0:#%}", i);     // 12345600%
        i = -123456;
        Console.WriteLine();
        Console.WriteLine("{0:#0}", i);             // -123456
        Console.WriteLine("{0:#0;(#0)}", i);        // (123456)
        Console.WriteLine("{0:#0;(#0);<zero>}", i); // (123456)
        Console.WriteLine("{0:#%}", i);             // -12345600%
        i = 0;
        Console.WriteLine();
        Console.WriteLine("{0:#0}", i);             // 0
        Console.WriteLine("{0:#0;(#0)}", i);        // 0
        Console.WriteLine("{0:#0;(#0);<zero>}", i); // <zero>
        Console.WriteLine("{0:#%}", i);             // %
    }
}

Use CultureInfo in int.ToString method

 
using System;
using System.Globalization;
public class NumParsingApp {
    public static void Main(string[] args) {
        int k = 12345;
        CultureInfo us = new CultureInfo("en-US");
        string v = k.ToString("c", us);
        Console.WriteLine(v);
    }
}

Use CultureInfo int ToString method

using System;
using System.Globalization;
using System.Threading;
class Program {
    static void Main(string[] args) {
        int val = 1234567890;
        Console.WriteLine(val.ToString("N"));
        Console.WriteLine(val.ToString("N",new CultureInfo("fr-FR")));
        Thread.CurrentThread.CurrentCulture = new CultureInfo("de-DE");
        Console.WriteLine(val.ToString("N"));
    }
}

Using Integers

using System;
public class UsingIntegers
{
  static void Main(string[] args)
  {
    int MyInt = 12345;
    long MyLong = MyInt;
    
  }
  public long My2ndFunction(long MyLong)
  {
    try
    {
      long c = checked(MyLong * 500);
    }
    catch (OverflowException e)
    {
      Console.WriteLine(e);
    }
    return 0;
  }
}

Using Variables

using System;
public class UsingVariables
{
  static void Main(string[] args)
  {
    int MyInt = 12345;
    int MyInt2 = MyInt + 1;
    int MyInt3;
    MyInt3 = My2ndFunction(MyInt2);
  }
  static public int My2ndFunction(int myInt2)
  {
    myInt2 = myInt2 * 2;
    return myInt2;
  }
}