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Random accesses in file using Seek() method in C#

In this article we will learn about, how to access file randomly? Here, we use Seek() method of FileStream class. Seek method set the current position file stream to given value.
Submitted by IncludeHelp, on November 17, 2017

FileStream.Seek()

This is a method of "FileStream" class, it is used to set the current position file stream to given value.

Syntax:

long Seek(long offset, SeekOrigin origin);

Parameters:

• Offset : move file stream to given value.
• Origin : It tells the origin, it may be start, current and end.

Example:

using System;
using System.IO;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main()
        {
            byte[] b1 = { 10, 20, 24, 13, 15, 17 };
            byte[] b2 = new byte[6];

            byte large = 0;
            FileStream f1;
            f1 = new FileStream("abc.txt", FileMode.Create, FileAccess.Write);

            f1.Write(b1,0,6);
            f1.Close();

            
            f1 = new FileStream("abc.txt", FileMode.Open, FileAccess.Read);

            f1.Seek(3, SeekOrigin.Begin);
            f1.Read(b2, 0, 3);

            large = b2[0];
            for (int i = 1; i < b2.Length; i++)
            { 
                if (large < b2[i])
                    large = b2[i];
            }

            Console.WriteLine("Largest Item is : " + large);
            f1.Close();
        }
    }
}

Output

Largest Item is : 17

In this program, we are performing read and write operation into file and moving stream to 3^rd position from start and find largest element.

In above program, we need to remember, when we use "FileStream" class then we need to include System.IO namespace in the program.

C# FileStream Class Program »

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