A programming language feature, parameter and capability, that means and represents a value-type that can be set to nothing/null (instead of, or in the place of) the full common range of their possible values. Objects and pointers can be set to NULL by default, pointing to nowhere exactly, or with no object assigned. Variable containing nothing in other words. Not for integers and Boolean for example.
A so-called Nullable Type or NULL-VALUE support allows and give flexibility to developers and programmers, to also make these value types NULL. Great application possibilities for database type work and requirements.
Relational database fields in SQL may have an entry that is empty or equal to = NULL, containing no value. In fact then returning a NULL value and correctly represent the behaviour of the database, not returning an exception or error.
Value types can be made nullable, using the NULLABLE generic type , even creating structures that are combinations of multiple values. It provides a certain level of flexibility. Type conversion dynamics enables Visual Basic and C# type programming and languages. Managing data, interfaces, system types, conversion, standard contracts compliance, interactions control with events and delegates, designing applications,
Key Exam Points
- Review the chapter overview of all Framework Fundamentals, Types (value, reference, conversion), how they are used, what they do, how to access, create, change and specify/program them effectively, resulting in improved security and performance.
- For the exam, study practical examples of nullable types to deepen your application and knowledge on the topic
- Take the practice test
Cast, Unboxing, Narrowing, Filtering Exceptions
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