How to get file length in C#

How to get file length in C#

using System;

using System.IO;

class GetFileLength

{

static void Main()

{

const string strFileName = "Myfile.txt";

FileInfo objfileInfo = new FileInfo(strFileName);

long s1 = objfileInfo.Length;

File.AppendAllText(strFileName, " Add new information....");

FileInfo f2 = new FileInfo(strFileName);

long s2 = f2.Length;

Console.WriteLine("Before and after: " + s1.ToString() + "" + s2.ToString());

long change = s2 - s1;

Console.WriteLine("Size increase: " + change.ToString());

}

}