Represents a value that is not a number (NaN). This field is constant.
Assembly: mscorlib (in mscorlib.dll)
A method or operator returns when the result of an operation is undefined. For example, the result of dividing zero by zero is , as the following example shows. (But note that dividing a non-zero number by zero returns either PositiveInfinity or NegativeInfinity, depending on the sign of the divisor.)
In addition, a method call with a value or an operation on a value returns , as the following example shows.
Use the IsNaN method to determine whether a value is not a number. The Equality operator considers two values to be unequal to one another. In general, Double operators cannot be used to compare with other Double values, although comparison methods (such as Equals and CompareTo) can. The following example illustrates the difference in behavior between Double comparison operators and methods.
.NET FrameworkSupported in: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0
.NET Framework Client ProfileSupported in: 4, 3.5 SP1
Portable Class LibrarySupported in: Portable Class Library
.NET for Windows Store appsSupported in: Windows 8
.NET for Windows Phone appsSupported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8
Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)