A formatter context. This object can be used to extract additional information about the environment this converter is being invoked from. This may be null, so you should always check. Also, properties on the context object may also return null.
true if the collection returned from GetStandardValues is an exhaustive list of possible values; otherwise, false if other values are possible. The default implementation for this method always returns false.
The context parameter is not used in the standard implementation of this method.
If the list is exclusive, then no other values are valid, such as in an Enum data type. If the list is not exclusive, then there are other valid values besides the list of standard values GetStandardValues provides.