Csharp/C Sharp/File Stream/FileStream

An enhanced cipher component that maintains a log file

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// An enhanced cipher component that maintains a log file.  
using CipherLib; // import CipherComp"s namespace  
  
using System;  
using System.ruponentModel;  
using System.IO;  
  
namespace CipherLib {  
  
  // An Cipher component that maintains a log file. 
  class CipherComp : Component {   
    static int useID = 0; 
    int id; // instance id 
    bool isDisposed; // true if component is disposed.  
    FileStream log; 
  
    // Constructor  
    public CipherComp() {  
      isDisposed = false; // component not disposed  
      try {  
        log = new FileStream("CipherLog" + useID, FileMode.Create);  
        id = useID; 
        useID++; 
      } catch (FileNotFoundException exc) {  
        Console.WriteLine(exc);  
        log = null; 
      }  
    }  
 
    // Destructor  
    ~CipherComp() {  
       Console.WriteLine("Destructor for component " 
                         + id); 
       Dispose(false);  
    }  
  
    // Encode the file. Return and store result. 
    public string Encode(string msg) {  
  
      string temp = "";  
  
      for(int i=0;i < msg.Length; i++)   
        temp += (char) (msg[i] + 1);          
  
      // Store in log file.  
      for(int i=0; i < temp.Length; i++)  
        log.WriteByte((byte) temp[i]);  
  
      return temp; 
    }  
  
    // Decode the message. Return and store result.  
    public string Decode(string msg) {  
  
      string temp = "";  
  
      for(int i=0; i < msg.Length; i++)  
        temp += (char) (msg[i] - 1);  
  
      // Store in log file.  
      for(int i=0; i < temp.Length; i++)  
        log.WriteByte((byte) temp[i]);  
 
      return temp; 
    }  
  
    protected override void Dispose(bool dispAll) {  
      Console.WriteLine("Dispose(" + dispAll + 
                        ") for component " + id); 
 
      if(!isDisposed) {  
        if(dispAll) {  
          Console.WriteLine("Closing file for " + 
                            "component " + id); 
          log.Close(); // close encoded file  
          isDisposed = true;  
        }  
        // no unmanaged resources to release  
        base.Dispose(dispAll);  
      }  
    }  
  }  
}
// Another client that uses CipherComp.  
  
  
public class CipherCompClient1 {  
  public static void Main() {  
    CipherComp cc = new CipherComp();  
  
    string text = "Testing";  
  
    string ciphertext = cc.Encode(text);  
    Console.WriteLine(ciphertext);  
  
    string plaintext = cc.Decode(ciphertext);  
    Console.WriteLine(plaintext);  
 
    text = "Components are powerful."; 
 
    ciphertext = cc.Encode(text);  
    Console.WriteLine(ciphertext);  
  
    plaintext = cc.Decode(ciphertext);  
    Console.WriteLine(plaintext);  
  
    cc.Dispose(); // free resources  
  }  
}

A simple disk-to-screen utility that demonstrates a FileReader

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
/* A simple disk-to-screen utility that 
   demonstrates a FileReader. */ 
 
using System; 
using System.IO;  
 
public class DtoS { 
  public static void Main() { 
    FileStream fin; 
    string s; 
 
    try { 
      fin = new FileStream("test.txt", FileMode.Open); 
    } 
    catch(FileNotFoundException exc) { 
      Console.WriteLine(exc.Message + "Cannot open file."); 
      return ; 
    }  
 
    StreamReader fstr_in = new StreamReader(fin); 
 
    // Read the file line-by-line. 
    while((s = fstr_in.ReadLine()) != null) { 
      Console.WriteLine(s); 
    } 
 
    fstr_in.Close(); 
  } 
}

Compare two files

/*
C# A Beginner"s Guide
By Schildt
Publisher: Osborne McGraw-Hill
ISBN: 0072133295
*/
/*   
   Project 11-1 
 
   Compare two files. 
 
   To use this program, specify the names   
   of the files to be compared on the command line. 
 
   For example: 
       CompFile FIRST.TXT SECOND.TXT  
*/  
  
using System; 
using System.IO;  
  
public class CompFiles {  
  public static void Main(string[] args) {  
    int i=0, j=0;  
    FileStream f1;  
    FileStream f2;  
  
    try {  
      // open first file 
      try {  
        f1 = new FileStream(args[0], FileMode.Open);  
      } catch(FileNotFoundException exc) {  
        Console.WriteLine(exc.Message);  
        return;  
      }  
  
      // open second file  
      try {  
        f2 = new FileStream(args[1], FileMode.Open);  
      } catch(FileNotFoundException exc) {  
        Console.WriteLine(exc.Message);  
        return;  
      }  
    } catch(IndexOutOfRangeException exc) {  
      Console.WriteLine(exc.Message + "\nUsage: CompFile f1 f2");  
      return;  
    }  
  
    // Compare files  
    try {  
      do {  
        i = f1.ReadByte();  
        j = f2.ReadByte();  
        if(i != j) break; 
      } while(i != -1 && j != -1);  
    } catch(IOException exc) {  
      Console.WriteLine(exc.Message);  
    }  
    if(i != j)  
      Console.WriteLine("Files differ."); 
    else 
      Console.WriteLine("Files are the same."); 
  
    f1.Close();  
    f2.Close();  
  }  
}

Create a file stream with new FileStream("test.bin", FileMode.Create)

 
using System;
using System.IO;
class MainClass {
    static void Main() {
        using (FileStream fs = new FileStream("test.bin", FileMode.Create)) {
            using (BinaryWriter w = new BinaryWriter(fs)) {
                w.Write(124.23M);
                w.Write("Tstring");
                w.Write("Tstring 2");
                w.Write("!");
            }
        }
        Console.WriteLine("Press Enter to read the information.");
        Console.ReadLine();
        using (FileStream fs = new FileStream("test.bin", FileMode.Open)) {
            using (StreamReader sr = new StreamReader(fs)) {
                Console.WriteLine(sr.ReadToEnd());
                Console.WriteLine();
                fs.Position = 0;
                using (BinaryReader br = new BinaryReader(fs)) {
                    Console.WriteLine(br.ReadDecimal());
                    Console.WriteLine(br.ReadString());
                    Console.WriteLine(br.ReadString());
                    Console.WriteLine(br.ReadChar());
                }
            }
        }
    }
}

Create StreamReader from File Stream

using System;
using System.IO;
public class IOExample
{
  static void Main() {   
    FileStream fs;
    StreamReader srIn;
    try {
      fs = new FileStream("practice.txt", FileMode.Open );
      srIn = new StreamReader(fs);
      string line = srIn.ReadLine();
      Console.WriteLine("line = "+line);
      srIn.Close();
    } catch (IOException ioe) {
      Console.WriteLine("IOException occurred: "+ioe.Message);
    }
  }
}

FileStream with FileMode.Create and FileMode.Open

using System;
using System.IO;
using System.Text;
class MainClass {
    static void Main() {
        using (FileStream fs = new FileStream("test.txt", FileMode.Create)) {
            using (StreamWriter w = new StreamWriter(fs, Encoding.UTF8)) {
                w.WriteLine(124.23M);
                w.WriteLine("Test string");
                w.WriteLine("!");
            }
        }
        Console.WriteLine("Press Enter to read the information.");
        Console.ReadLine();
        // Open the file in read-only mode.
        using (FileStream fs = new FileStream("test.txt", FileMode.Open)) {
            using (StreamReader r = new StreamReader(fs, Encoding.UTF8)) {
                // Read the data and convert it to the appropriate data type.
                Console.WriteLine(Decimal.Parse(r.ReadLine()));
                Console.WriteLine(r.ReadLine());
                Console.WriteLine(Char.Parse(r.ReadLine()));
            }
        }
    }
}

illustrates reading and writing binary data

/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/

 /*
  Example15_15.cs illustrates reading and writing binary data
*/
using System;
using System.IO;
public class Example15_15 
{
  public static void Main() 
  {
    // create a new file to work with
    FileStream outStream = File.Create("c:\\BinaryTest.dat");
    // use a BinaryWriter to write formatted data to the file
    BinaryWriter bw = new BinaryWriter(outStream);
    // write various data to the file
    bw.Write( (int) 32);
    bw.Write( (decimal) 4.567);
    string s = "Test String";
    bw.Write(s);
    // flush and close
    bw.Flush();
    bw.Close();
    // now open the file for reading
    FileStream inStream = File.OpenRead("c:\\BinaryTest.dat");
    // use a BinaryReader to read formatted data and dump it to the screen
    BinaryReader br = new BinaryReader(inStream);
    int i = br.ReadInt32();
    decimal d = br.ReadDecimal();
    string s2 = br.ReadString();
    Console.WriteLine(i);
    Console.WriteLine(d);
    Console.WriteLine(s2);
    // clean up
    br.Close();
  }
}

illustrates use of FileStreams

/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
 /*
  Example15_10.cs illustrates use of FileStreams
*/
using System;
using System.Windows.Forms;
using System.IO;
public class Example15_10 
{
    [STAThread]
  public static void Main() 
  {
    // use an open file dialog to get a filename
    OpenFileDialog dlgOpen = new OpenFileDialog();
    dlgOpen.Title="Select file to back up";
    if (dlgOpen.ShowDialog() == DialogResult.OK)
    {
      FileStream inStream = File.OpenRead(dlgOpen.FileName);
      FileStream outStream = 
       File.OpenWrite(dlgOpen.FileName + ".bak");
      int b;
      // copy all data from in to out
      while ((b = inStream.ReadByte()) > -1)
        outStream.WriteByte( (byte) b);
      // clean up
      outStream.Flush();
      outStream.Close();
      inStream.Close();
    }
  }
}

illustrates use of FileStreams 2

/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
 /*
  Example15_11.cs illustrates use of FileStreams
*/
using System;
using System.Windows.Forms;
using System.IO;
public class Example15_11 
{
    [STAThread]
  public static void Main() 
  {
    // use an open file dialog to get a filename
    OpenFileDialog dlgOpen = new OpenFileDialog();
    dlgOpen.Title="Select file to back up";
    if (dlgOpen.ShowDialog() == DialogResult.OK)
    {
      FileStream inStream = File.OpenRead(dlgOpen.FileName);
      FileStream outStream = 
        File.OpenWrite(dlgOpen.FileName + ".bak");
      byte[] buf = new byte[4096];
      int bytesRead;
      // copy all data from in to out
      while ((bytesRead = inStream.Read(buf, 0, 4096)) > 0)
        outStream.Write(buf, 0, bytesRead);
      // clean up
      outStream.Flush();
      outStream.Close();
      inStream.Close();
    }
  }
}

Reading and Writing Files

using System;
using System.IO;
public class ReadingWritingFiles
{
    public static void Main()
    {
        FileStream f = new FileStream("output.txt", FileMode.Create);
        StreamWriter s = new StreamWriter(f);
        
        s.WriteLine("{0} {1}", "test", 55);
        s.Close();
        f.Close();
    }
}

Reads lines separated by vertical bars

using System;
using System.IO;
public class FileReadAddresses {
  public static void Main( ) {
    String line;
    String street, city, state, zip;
    StreamReader f = new StreamReader("test.data");
    while ((line=f.ReadLine())!= null){
      String[] strings = line.Split(new char[]{"|"});
      if (strings.Length == 4) {
        street = strings[0];
        city = strings[1];
        state = strings[2];
        zip = strings[3];
        Console.WriteLine(street); 
        Console.WriteLine(city);
        Console.WriteLine(state);
        Console.WriteLine(zip);
      }
    }
    f.Close();
  }
}    
//File: test.data
/*
4665 Street|Toronto|ON|90048
*/

Reads strings from a file created in a text editor

using System;
using System.IO;
public class FileReadStrings {
  public static void Main( ) {
    String line;
    StreamReader f = new StreamReader("test.data");        
    while((line=f.ReadLine()) != null)                           
      Console.WriteLine(line);
    f.Close(); 
  }
}
//File: test.data
/*
4665 Street|Toronto|ON|90048
*/

Seek from Begin

 

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;

class Program {
    static void Main(string[] args) {
        byte[] byData = new byte[200];
        char[] charData = new Char[200];
        try {
            FileStream aFile = new FileStream("Program.cs", FileMode.Open);
            aFile.Seek(135, SeekOrigin.Begin);
            aFile.Read(byData, 0, 200);
        } catch (IOException e) {
            Console.WriteLine("An IO exception has been thrown!");
            Console.WriteLine(e.ToString());
            Console.ReadKey();
            return;
        }
        Decoder d = Encoding.UTF8.GetDecoder();
        d.GetChars(byData, 0, byData.Length, charData, 0);
        Console.WriteLine(charData);
    }
}

Set File IO Permission to c:

using System;
using System.Collections.Generic;
using System.Text;
using System.Security.Permissions;

class Program {
    static void Main(string[] args) {
        MyClass.Method();
    }
}
[FileIOPermission(SecurityAction.Assert, Read = "C:/")]
class MyClass {
    public static void Method() {
        // implementation goes here
    }
}

Using FileStreams

/*
 * C# Programmers Pocket Consultant
 * Author: Gregory S. MacBeth
 * Email: gmacbeth@comporium.net
 * Create Date: June 27, 2003
 * Last Modified Date:
 * Version: 1
 */
using System;
using System.IO;
namespace Client.Chapter_11___File_and_Streams
{
  public class UsingFileStreams {
    static void Main(string[] args)
    {
      //Creates a file with read-write access that allows others to read
      FileStream MyFileStream1 = new FileStream(@"c:\Projects\Testing.txt", FileMode.Create);
      FileInfo MyFiles = new FileInfo(@"c:\Projects\Testing.txt");
      FileStream MyFileStream2 = MyFiles.OpenRead();
      //or any of the following
      MyFileStream2 = MyFiles.OpenWrite();
      MyFileStream2 = MyFiles.Open(FileMode.Append, FileAccess.Read, FileShare.None);
      MyFileStream2 = MyFiles.Create();
      //You can read file stream ona pe byte basis or as an array of bytes
      int MyBytes = MyFileStream1.ReadByte();
      //or
      int NumberOfBytes = 200;
      byte[] MyByteArray = new Byte[NumberOfBytes];
      int BytesRead = MyFileStream1.Read(MyByteArray, 0, NumberOfBytes);
      //Data can be written to FileStreams as well through bytes or arrays of //bytes
      byte MyWriteByte = 100;
      MyFileStream1.WriteByte(MyWriteByte);
      //or via an array
      int NumberOfBytesToWrite = 256;
      byte[] MyWriteByteArray = new Byte[NumberOfBytesToWrite];
      for (int i = 0; i < 256; i++)
      {
        MyWriteByteArray[i] = (byte)i;
        i++;
      }
      MyFileStream1.Write(MyWriteByteArray, 0, NumberOfBytesToWrite);
      MyFileStream1.Close();
      MyFileStream2.Close();
    }
  }
}

Write byte array to a file

 

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
class Program {
    static void Main(string[] args) {
        byte[] byData;
        char[] charData;
        try {
            FileStream aFile = new FileStream("Temp.txt", FileMode.Create);
            charData = "www.nfex.ru".ToCharArray();
            byData = new byte[charData.Length];
            Encoder e = Encoding.UTF8.GetEncoder();
            e.GetBytes(charData, 0, charData.Length, byData, 0, true);
            aFile.Seek(0, SeekOrigin.Begin);
            aFile.Write(byData, 0, byData.Length);
        } catch (IOException ex) {
            Console.WriteLine(ex.ToString());
            return;
        }
    }
}