For internal use. Abstract class representing the full context in which a C1DocumentSource operates. Instances of this class can be used to save and restore the current state of a C1DocumentSource, for example it can be used to implement forward and backward navigation. For details see C1.WPF.Document.C1DocumentSource.GetContext() and SetContext(C1DocumentSourceContext) methods. Derived classes should override Equals(...) and GetHashCode(...).