I know this is old thread already. but maybe someone will look for solution. And here's what I use and the easiest way
public static string FormatFileSize(long bytes)
{
var unit = 1024;
if (bytes < unit) { return $"{bytes} B"; }
var exp = (int)(Math.Log(bytes) / Math.Log(unit));
return $"{bytes / Math.Pow(unit, exp):F2} {("KMGTPE")[exp - 1]}B";
}
Get folder size (for example usage)
public static long GetFolderSize(string path, string ext, bool AllDir)
{
var option = AllDir ? SearchOption.AllDirectories : SearchOption.TopDirectoryOnly;
return new DirectoryInfo(path).EnumerateFiles("*" + ext, option).Sum(file => file.Length);
}
EXAMPLE USAGE:
public static void TEST()
{
string folder = @"C:\Users\User\Videos";
var bytes = GetFolderSize(folder, "mp4", true); //or GetFolderSize(folder, "mp4", false) to get all single folder only
var totalFileSize = FormatFileSize(bytes);
Console.WriteLine(totalFileSize);
}