Single - IsNaN

Returns a value that indicates whether the specified value is not a number ().

Try it

public static void Main()
{

    Console.WriteLine("It returns a value indicating whether a value is not-a-number.\n");

    Display(32.0f, 12);
	Display(32.0f, 0);
	Display(-5f, 0);
	Display(0.0f, 0);
}

public static void Display(float f1, float f2)
{
	// C# Extension Method: Single - IsNaN
    bool result = (f1 / f2).IsNaN();

    Console.WriteLine("{0}/{1} = {2}", f1, f2, result);
}

View Source
using System;

public static partial class Extensions
{
    /// <summary>
    ///     Returns a value that indicates whether the specified value is not a number ().
    /// </summary>
    /// <param name="f">A single-precision floating-point number.</param>
    /// <returns>true if  evaluates to not a number (); otherwise, false.</returns>
    public static Boolean IsNaN(this Single f)
    {
        return Single.IsNaN(f);
    }
}