Encapsulating Raw Streams
While the Stream class reads and
writes raw bytes, most programs prefer
to produce and consume data either in the form of native data types
or lines of text. To make this easy, the framework includes related
pairs of XXXReader/XXXWriter
classes that provide this higher-level, encapsulated access to the
raw underlying data stream.
The BinaryReader and BinaryWriter Classes
BinaryReader and BinaryWriter
are
concrete
classes that define operations for reading and writing a stream of
native data types. The most fundamental operations of the
BinaryReader and BinaryWriter
classes are the methods that read and write instances of the
primitive data types: bool,
byte, char,
decimal, float,
double, short,
int, long,
sbyte, ushort,
uint, and ulong. Additionally,
methods are provided to read and write strings and
arrays of the primitive data types.
Imagine we have a simple class, defined as follows, that we want to read and write from a stream:
public class Student {
public string Name;
public int Age;
public double GPA;
}Methods that read and write instances of the
Student class from a stream in a binary format
might look like this:
void SaveToStream(Stream stm, Student s) { BinaryWriter bw = new BinaryWriter(stm); bw.Write(s.Name); bw.Write(s.Age); bw.Write(s.GPA); bw.Flush( ); // Ensure the BinaryWriter buffer is empty } void ReadFromStream(Stream stm, Student s) { BinaryReader br = new BinaryReader(stm); s.Name = br.ReadString( ); s.Age = br.ReadInt32( ); s.GPA ...