C# / .NET - check if number is even

In this short article, we would like to show how check if number is even using C# / .NET.

Quick solution:

int number = 5;

if (number % 2 == 0)
{
	// ...
}

Even numbers:

... -8  -6  -4  -2   0   2   4   6   8 ...

Practical example

using System;

public class Program
{
    public static void Main(String[] args)
	{    
		Console.WriteLine( NumberUtils.IsEven(0) );   // true      // even
		Console.WriteLine( NumberUtils.IsEven(1) );   // false
		Console.WriteLine( NumberUtils.IsEven(2) );   // true      // even
		Console.WriteLine( NumberUtils.IsEven(3) );   // false
		Console.WriteLine( NumberUtils.IsEven(4) );   // true      // even
		Console.WriteLine( NumberUtils.IsEven(5) );   // false

		Console.WriteLine( NumberUtils.IsEven(-1) );  // false
		Console.WriteLine( NumberUtils.IsEven(-2) );  // true      // even
		Console.WriteLine( NumberUtils.IsEven(-3) );  // false
		Console.WriteLine( NumberUtils.IsEven(-4) );  // true      // even
		Console.WriteLine( NumberUtils.IsEven(-5) );  // false
    }
}

public class NumberUtils
{
	public static bool IsEven(int number)
	{
		return number % 2 == 0;
	}
}

Alternative solution

In this section, you can find solution that uses bitwise operator.

using System;

public class Program
{
    public static void Main(String[] args)
	{    
		Console.WriteLine( NumberUtils.IsEven(0) );   // true      // even
		Console.WriteLine( NumberUtils.IsEven(1) );   // false
		Console.WriteLine( NumberUtils.IsEven(2) );   // true      // even
		Console.WriteLine( NumberUtils.IsEven(3) );   // false
		Console.WriteLine( NumberUtils.IsEven(4) );   // true      // even
		Console.WriteLine( NumberUtils.IsEven(5) );   // false

		Console.WriteLine( NumberUtils.IsEven(-1) );  // false
		Console.WriteLine( NumberUtils.IsEven(-2) );  // true      // even
		Console.WriteLine( NumberUtils.IsEven(-3) );  // false
		Console.WriteLine( NumberUtils.IsEven(-4) );  // true      // even
		Console.WriteLine( NumberUtils.IsEven(-5) );  // false
    }
}

public class NumberUtils
{
	public static bool IsEven(int number)
	{
		return (number & 1) == 0;
	}
}

See also

1. C# / .NET - check if number is odd