In order to calculate a file’s size in C#, you can use the FileInfo object and create some logic to calculate the physical KB, MB or GB of a file. You can use the following code:
using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Windows.Forms;using System.IO;namespace GetFilesize{ public partial class Form1 : Form { public Form1() { InitializeComponent(); } public static string GetFileSizeInBytes(long TotalBytes) { if (TotalBytes = 1073741824) //Giga Bytes { Decimal FileSize = Decimal.Divide(TotalBytes, 1073741824); return String.Format("{0:##.##} GB", FileSize); } else if (TotalBytes = 1048576) //Mega Bytes { Decimal FileSize = Decimal.Divide(TotalBytes, 1048576); return String.Format("{0:##.##} MB", FileSize); } else if (TotalBytes = 1024) //Kilo Bytes { Decimal FileSize = Decimal.Divide(TotalBytes, 1024); return String.Format("{0:##.##} KB", FileSize); } else if (TotalBytes 0 & TotalBytes { Decimal FileSize = TotalBytes; return String.Format("{0:##.##} Bytes", FileSize); } else { return "0 Bytes"; } } private void button1_Click(object sender, EventArgs e) { // The name of the file const string FileName = "C:\INSTALL.LOG"; // Create new FileInfo object and get the Length. FileInfo fInfo = new FileInfo(FileName); long Result = fInfo.Length; //Display In Label label1.Text = GetFileSizeInBytes(Result); } }}