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==C#"s I/O Is Built Upon Streams==

<OL><LI>C# programs perform I/O through streams.</LI><LI>A stream is linked to a physical device by the C# I/O system.</LI><LI>The I/O classes and methods can be applied to many types of devices.</LI></OL>
At the lowest level, all C# I/O systems operate on bytes.
The Predefined Streams
<OL><LI>Console.Out: the standard output stream.</LI><LI>Console.In: standard input, which is by default the keyboard.</LI><LI>Console.Error: the standard error stream, which is also the console by default.</LI></OL>
15.18.Stream
15.18.1.
C#"s I/O Is Built Upon Streams
15.18.2.
<A href="/Tutorial/CSharp/0300__File-Directory-Stream/TheStreamClasses.htm">The Stream Classes</a>
15.18.3.
<A href="/Tutorial/CSharp/0300__File-Directory-Stream/TheByteStreamClassesandTheCharacterStreamWrapperClasses.htm">The Byte Stream Classes and The Character Stream Wrapper Classes</a>
15.18.4.
<A href="/Tutorial/CSharp/0300__File-Directory-Stream/StreamseekingSeekOriginCurrentSeekOriginBeginSeekOriginEnd.htm">Stream seeking: SeekOrigin.Current, SeekOrigin.Begin, SeekOrigin.End</a>
15.18.5.
<A href="/Tutorial/CSharp/0300__File-Directory-Stream/Usingstreamreadertodecodestreams.htm">Using streamreader to decode streams</a>
15.18.6.
<A href="/Tutorial/CSharp/0300__File-Directory-Stream/Usingstreamreadertoreadentirelinesatatime.htm">Using streamreader to read entire lines at a time</a>
15.18.7.
<A href="/Tutorial/CSharp/0300__File-Directory-Stream/Usingstreamreadertoreadtheentirestreamatonce.htm">Using streamreader to read the entire stream at once</a>
15.18.8.
<A href="/Tutorial/CSharp/0300__File-Directory-Stream/Readingfromastreamcastingtochars.htm">Reading from a stream, casting to chars</a>
15.18.9.
<A href="/Tutorial/CSharp/0300__File-Directory-Stream/Readingfromastreambufferatatime.htm">Reading from a stream buffer at a time</a>
15.18.10.
<A href="/Tutorial/CSharp/0300__File-Directory-Stream/ImplementingBinaryReadWriteToFile.htm">Implementing Binary Read Write To File</a>

==Implementing Binary Read Write To File==

<source lang="csharp">using System;
using System.IO;

class Tester
{
public static void Main()
{
int SizeBuff = 1024;
Stream inputStream = File.OpenRead("test1.cs");
Stream outputStream = File.OpenWrite("test1.bak");
byte[] buffer = new Byte[SizeBuff];
int bytesRead;
while ((bytesRead =
inputStream.Read(buffer, 0, SizeBuff)) > 0)
{
outputStream.Write(buffer, 0, bytesRead);
}
inputStream.Close();
outputStream.Close();
}
}</source>

==Reading from a stream buffer at a time==

<source lang="csharp">using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.IO;
using System.IO.rupression;
using System.Net;
using System.Net.Mail;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
public class MainClass
{
public static void Main()
{
using (Stream s = new FileStream("c:\\test.txt", FileMode.Open))
{
int readCount;
byte[] buffer = new byte[4096];
while ((readCount = s.Read(buffer, 0, buffer.Length)) != 0)
{
for (int i = 0; i < readCount; i++)
{
Console.Write("{0} ", buffer[i]);
}
}
}
}
}</source>

==Reading from a stream, casting to chars==

<source lang="csharp">using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.IO;
using System.IO.rupression;
using System.Net;
using System.Net.Mail;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
public class MainClass
{
public static void Main()
{
using (Stream s = new FileStream("c:\\test.txt", FileMode.Open))
{
int read;
while ((read = s.ReadByte()) != -1)
{
Console.Write("{0} ", (char)read);
}
}
}
}</source>

==Stream seeking: SeekOrigin.Current, SeekOrigin.Begin, SeekOrigin.End==

<source lang="csharp">using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.IO;
using System.IO.rupression;
using System.Net;
using System.Net.Mail;
using System.Net.Sockets;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
public class MainClass
{
public static void Main()
{
using (Stream s = new FileStream("c:\\test.txt", FileMode.Open))
{
s.Seek(8, SeekOrigin.Current);
Console.WriteLine(s.ReadByte());
s.Seek(0, SeekOrigin.Begin);
Console.WriteLine(s.ReadByte());
s.Seek(-1, SeekOrigin.End);
Console.WriteLine(s.ReadByte());
}
}
}</source>

==The Byte Stream Classes and The Character Stream Wrapper Classes==

The Byte Stream Classes
Stream Class
Description
BufferedStream
Wraps a byte stream and adds buffering.
FileStream
A byte stream designed for file I/O.
MemoryStream
A byte stream that uses memory for storage.
The Character Stream Wrapper Classes.
To create a character stream, wrap a byte stream inside one of C#"s character stream wrappers.
<OL><LI>The abstract classes TextReader and TextWriter are at the top of the character stream hierarchy.</LI><LI>TextReader handles input.</LI><LI>TextWriter handles output.</LI></OL>

==The Stream Classes==

<OL><LI>System.IO.Stream represents a byte stream</LI><LI>System.IO.Stream is a base class for all other stream classes.</LI><LI>System.IO.Stream is abstract.</LI></OL>
Some of the Methods Defined by Stream
Method
Description
void Close()
Closes the stream.
void Flush()
Flush the stream.
int ReadByte()
Returns an integer representation of a byte of input. Returns -1 if no byte is available.
int Read(byte[ ] buf,int offset, int numBytes)
Attempts to read up to numBytes bytes into buf starting at buf[offset], returning the number of bytes successfully read.
long Seek(long offset,SeekOrigin origin)
Sets the current position in the stream to the specified offset from the specified origin.
void WriteByte(byte b)
Writes a single byte to an output stream.
void Write(byte[ ] buf,int offset, int numBytes)
Writes a subrange of numBytes bytes from the array buf, beginning at buf[offset].
The Properties Defined by Stream
Method
Description
bool CanRead
can be read or not. (read-only)
bool CanSeek
supports position requests or not. (read-only)
bool CanWrite
can be written or not. (read-only)
long Length
the length of the stream. (read-only)
long Position
the current position of the stream. (read/write)

==Using streamreader to decode streams==

<source lang="csharp">using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.IO;
using System.IO.rupression;
using System.Net;
using System.Net.Mail;
using System.Net.Sockets;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
public class MainClass
{
public static void Main()
{
Stream s = new FileStream("c:\\test.txt", FileMode.Open);
using (StreamReader sr = new StreamReader(s, Encoding.UTF8))
{
int readCount;
char[] buffer = new char[1024];
while ((readCount = sr.Read(buffer, 0, 1024)) != 0)
{
for (int i = 0; i < readCount; i++)
{
Console.Write("{0} ", buffer[i]);
}
}
}
}
}</source>

==Using streamreader to read entire lines at a time==

<source lang="csharp">using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.IO;
using System.IO.rupression;
using System.Net;
using System.Net.Mail;
using System.Net.Sockets;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
public class MainClass
{
public static void Main()
{
Stream s = new FileStream("c:\\test.txt", FileMode.Open);
using (StreamReader sr = new StreamReader(s, Encoding.UTF8))
{
string line;
while ((line = sr.ReadLine()) != null)
{
Console.WriteLine(line);
}
}
}
}</source>

==Using streamreader to read the entire stream at once==

<source lang="csharp">using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.IO;
using System.IO.rupression;
using System.Net;
using System.Net.Mail;
using System.Net.Sockets;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
public class MainClass
{
public static void Main()
{

Stream s = new FileStream("c:\\test.txt", FileMode.Open);
using (StreamReader sr = new StreamReader(s, Encoding.UTF8))
{
Console.WriteLine(sr.ReadToEnd());
}
}
}</source>

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