When overridden in a derived class, gets a value indicating whether the handle value is invalid.
Assembly: mscorlib (in mscorlib.dll)
Derived classes must implement the 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 property calculates whether the given handle value is always considered invalid. Therefore, the property always returns the same value for any one handle value.
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