Assembly: mscorlib (in mscorlib.dll)
Derived classes must implement the IsInvalid property so that the common language runtime can determine whether critical finalization is required. Derived classes must provide an implementation that suits the general type of handle they support (0 or -1 is invalid). These classes can then be further derived for specific safe handle types.
Unlike the IsClosed property, which reports whether the SafeHandle object has finished using the underlying handle, the IsInvalid property calculates whether the given handle value is always considered invalid. Therefore, the IsInvalid property always returns the same value for any one handle value.
Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.