Double.NaN Field

The value of this constant is the result of dividing zero by zero.

This constant is returned when the result of an operation is undefined.

Use IsNaN to determine whether a value is not a number. It is not possible to determine whether a value is not a number by comparing it to another value equal to NaN.

The following example illustrates the use of NaN:

Double zero = 0;

// This condition will return false.
if ((0 / zero) == Double.NaN)
{
   outputBlock.Text += "0 / 0 can be tested with Double.NaN." + "\n";
}
else
{
   outputBlock.Text += "0 / 0 cannot be tested with Double.NaN; use Double.IsNan() instead." + "\n";
}

Silverlight

Silverlight for Windows Phone

XNA Framework

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Reference