Knowledge Check - Other Features

1. True/False. The const keyword is equivalent to the readonly keyword.

False. const is for compile-time constants. readonly is a runtime constant. With const, the compiler determines what value the constant has and substitutes that value anywhere the code refers to it. It is slightly faster than readonly, but is also much more limited.

2. What is the name of the class that lets you inspect (reflection) a type’s definition at runtime?

The System.Type class is the primary origination point of reflection. Instances of System.Type represent the metadata for a specific type available in the program.

3. What keyword allows you to jump to a named location elsewhere in the method?

goto. But don’t use it. Find a way to structure the code to avoid it, and use loops, ifs, returns, breaks, continues, and other similar features. You always end up regretting goto eventually.

4. What keyword will enable you to split a class’s definition into multiple parts?

The partial keyword lets you split a type definition across multiple files (or even multiple slices within a single file, though the first is more common).

5. Name two bit manipulation operators.

There are quite a few. The bitshift operators >> and <<, and the logical operators &, |, ^, and &.

6. True/False. An enumeration definition can contain a class definition.

False. While a class can contain other type definitions, including an enumeration or another class, enumerations cannot include additional type definitions.

7. True/False. A class definition can contain an enumeration definition.

True. Classes can contain other type definitions inside of them as members. This is typically done only when the nested type is very closely related to the containing type.

8. What preprocessor directives begin and end a section of DEBUG-only code?

#if DEBUG starts a block that is only included when the DEBUG symbol is defined, and #endif will end it.

9. What keyword is involved when automatically cleaning up objects that implement IDisposable?

The using keyword is reused for automatically cleaning up IDisposable, as a part of using statements (contrasted with using directives at the top of the file).

10. True/False. You can create never-ending sequences with the yield keyword.

True. And this is one of the coolest features of IEnumerables and the yield keyword. You can produce arbitrarily long sequences.