Double - IsInfinity

Returns a value indicating whether the specified number evaluates to negative or positive infinity.

Try it

public static void Main()
{

    Console.WriteLine("It returns a value indicating whether the specified number evaluates to negative or positive infinity.\n");

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

public static void Display(double d1, double d2)
{
	// C# Extension Method: Double - IsInfinity
    bool result = (d1 / d2).IsInfinity();

    Console.WriteLine("{0}/{1} = {2}", d1, d2, result);
}

View Source 
using System;

public static partial class Extensions
{
    /// <summary>
    ///     Returns a value indicating whether the specified number evaluates to negative or positive infinity.
    /// </summary>
    /// <param name="d">A double-precision floating-point number.</param>
    /// <returns>true if  evaluates to  or ; otherwise, false.</returns>
    public static Boolean IsInfinity(this Double d)
    {
        return Double.IsInfinity(d);
    }
}