This documentation is archived and is not being maintained.
Returns a value indicating whether the specified number evaluates to a value that is not a number (
Public Shared Function IsNaN ( _
d As Double _
) As Boolean
Parameters d Type: System .Double A double-precision floating-point number.
Floating-point operations return
to signal that that result of the operation is undefined. For example, dividing 0.0 by 0.0 results in NaN . NaN
The following code example illustrates the use of
' This will return true.
If Double.IsNaN(0 / zero) Then
Console.WriteLine( "Double.IsNan() can determine whether a value is not-a-number.")
Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0
.NET Framework Client Profile
Supported in: 4, 3.5 SP1
Portable Class Library
Supported in: Portable Class Library
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see
.NET Framework System Requirements.