Demonstrate random access : File Read Write « File Stream « C# / C Sharp






Demonstrate random access

Demonstrate random access
  
/*
C#: The Complete Reference 
by Herbert Schildt 

Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/

// Demonstrate random access. 
 
using System; 
using System.IO;  
 
public class RandomAccessDemo { 
  public static void Main() { 
    FileStream f; 
    char ch;
 
    try { 
      f = new FileStream("random.dat", FileMode.Create); 
    } 
    catch(IOException exc) { 
      Console.WriteLine(exc.Message); 
      return ; 
    } 
 
    // Write the alphabet.      
    for(int i=0; i < 26; i++) { 
      try { 
        f.WriteByte((byte)('A'+i)); 
      }  
      catch(IOException exc) { 
        Console.WriteLine(exc.Message); 
        return ; 
      } 
    } 
 
    try { 
      // Now, read back specific values 
      f.Seek(0, SeekOrigin.Begin); // seek to first byte 
      ch = (char) f.ReadByte(); 
      Console.WriteLine("First value is " + ch); 
 
      f.Seek(1, SeekOrigin.Begin); // seek to second byte 
      ch = (char) f.ReadByte(); 
      Console.WriteLine("Second value is " + ch); 
 
      f.Seek(4, SeekOrigin.Begin); // seek to 5th byte 
      ch = (char) f.ReadByte(); 
      Console.WriteLine("Fifth value is " + ch); 
 
      Console.WriteLine(); 
 
      // Now, read every other value. 
      Console.WriteLine("Here is every other value: "); 
      for(int i=0; i < 26; i += 2) { 
        f.Seek(i, SeekOrigin.Begin); // seek to ith double 
        ch = (char) f.ReadByte(); 
        Console.Write(ch + " "); 
      } 
    }  
    catch(IOException exc) { 
      Console.WriteLine(exc.Message); 
    } 
  
    Console.WriteLine(); 
    f.Close(); 
  } 
}


           
         
    
  








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