BinaryWriter

void Write(sbyte val)        
void Write(byte val)
void Write(byte[ ] buf)
void Write(short val)
void Write(ushort val)
void Write(int val)
void Write(uint val)
void Write(long val)
void Write(ulong val)
void Write(float val)
void Write(double val)
void Write(char val)
void Write(char[ ] buf)
void Write(string val)

using System; /*  j a va2  s  .  c  o  m*/
using System.IO;  
 
class MainClass { 
  public static void Main() { 
    BinaryWriter dataOut; 
    BinaryReader dataIn; 
 
    int i = 10; 
    double d = 1.56; 
    bool b = true; 
 
    try { 
      dataOut = new BinaryWriter(new FileStream("testdata", FileMode.Create)); 
    } 
    catch(IOException exc) { 
      Console.WriteLine(exc.Message + "\nCannot open file."); 
      return; 
    } 
 
    try { 
      dataOut.Write(i);  
      dataOut.Write(d); 
      dataOut.Write(b); 
      dataOut.Write(12.2 * 7.4); 
    } 
    catch(IOException exc) { 
      Console.WriteLine(exc.Message + "\nWrite error."); 
    } 
 
    dataOut.Close(); 
 
    try { 
      dataIn = new BinaryReader(new FileStream("testdata", FileMode.Open)); 
    } 
    catch(FileNotFoundException exc) { 
      Console.WriteLine(exc.Message + "\nCannot open file."); 
      return; 
    } 
 
    try { 
      i = dataIn.ReadInt32(); 
      Console.WriteLine("Reading " + i); 
 
      d = dataIn.ReadDouble(); 
      Console.WriteLine("Reading " + d); 
 
      b = dataIn.ReadBoolean(); 
      Console.WriteLine("Reading " + b); 
 
      d = dataIn.ReadDouble(); 
      Console.WriteLine("Reading " + d); 
    } 
    catch(IOException exc) { 
      Console.WriteLine(exc.Message + "Read error."); 
    } 
 
    dataIn.Close();  
  } 
}

using System;//j  ava2s.  c  o m
using System.IO;

public class MainClass
{
    public static int Main(string[] args)
    {
    FileStream myFStream = new FileStream("temp.dat", FileMode.OpenOrCreate,FileAccess.ReadWrite);
    
    BinaryWriter binWrit = new BinaryWriter(myFStream);
    binWrit.Write("Hello as binary info...");
    
    int myInt = 9;
    float myFloat = 9.8F;
    bool myBool = false;
    char[] myCharArray = {'H', 'e', 'l', 'l', 'o'};
    
    binWrit.Write(myInt);
    binWrit.Write(myFloat);
    binWrit.Write(myBool);
    binWrit.Write(myCharArray);
      
      binWrit.BaseStream.Position = 0;

    Console.WriteLine("Reading binary data...");
    BinaryReader binRead = new BinaryReader(myFStream);
    int temp = 0;
    while(binRead.PeekChar() != -1)
    {
      Console.Write(binRead.ReadByte());  
      temp = temp + 1;
      if(temp ==  5)
      {
        temp = 0;
        Console.WriteLine();
      }
    }

    binWrit.Close();
    binRead.Close();
    myFStream.Close();

        return 0;
    }
}