Chapter 10 - Working with Files, Streams, and Serialization

1. What is the difference between using the File class and the FileInfo class?

   • The File class has static methods so it cannot be instantiated. It is best used for one-off tasks such as copying a file. The FileInfo class requires the instantiation of an object that represents a file. It is best used when you need to perform multiple operations on the same file.

2. What is the difference between the ReadByte method and the Read method of a stream?

   • The ReadByte method returns a single byte each time it is called and the Read method fills a temporary array with bytes up to a specified length. It is generally best to use Read to process blocks of bytes at once.

3. When would you use the StringReader, TextReader, and StreamReader classes?

   • StringReader is used for efficiently reading from a string stored in memory

   • TextReader is an abstract class that StringReader and StreamReader both inherit from for their shared functionality

   • StreamReader is used for reading strings from a stream that can be any type of text file, including XML and JSON

4. What does the DeflateStream type do?

   • DeflateStream implements the same compression algorithm as GZIP but without a cyclical redundancy check, so although it produces smaller compressed files, it cannot perform integrity checks when decompressing.

5. How many bytes per character does the UTF-8 encoding use?

   • It depends on the character. Most Western alphabet characters are stored using a single byte. Other characters may need two or more bytes.

6. What is an object graph?

   • An object graph is any instance of classes in memory that reference each other, thereby forming a set of related objects. For example, a Customer object may have a property that references a set of Order instances.

7. What is the best serialization format to choose for minimizing space requirements?

   • JavaScript Object Notation (JSON).

8. What is the best serialization format to choose for cross-platform compatibility?

   • eXtensible Markup Language (XML), although JSON is even better these days.