using Log to solve the problem

static String BytesToString(long byteCount)
{
string[] suf = { “B”, “KB”, “MB”, “GB”, “TB”, “PB”, “EB” }; //Longs run out around EB
if (byteCount == 0)
return “0” + suf[0];

long bytes = Math.Abs(byteCount);
int place = Convert.ToInt32(Math.Floor(Math.Log(bytes, 1024)));
double num = Math.Round(bytes / Math.Pow(1024, place), 1);
return (Math.Sign(byteCount) * num).ToString() + suf[place];
}

Another solution

This may not the most efficient way to do it, but it’s easier to read if you are not familiar with log maths, and should be fast enough for most scenarios.

string[] sizes = { “B”, “KB”, “MB”, “GB”, “TB” };
double len = new FileInfo(filename).Length;
int order = 0;
while (len >= 1024 && order < sizes.Length – 1) {
order++;
len = len/1024;
}

// Adjust the format string to your preferences. For example “{0:0.#}{1}” would

// show a single decimal place, and no space.

string result = String.Format(“{0:0.##} {1}”, len, sizes[order]);

Step 1:
You will need to import the following namespace.
using Microsoft.AspNetCore.Hosting;

Step 2:
By Using IHostingEnvironment
public class HomeController : Controller
{
private IHostingEnvironment Environment;
public HomeController(IHostingEnvironment _environment)
{
Environment = _environment;
}
public IActionResult Index()
{
string wwwPath = this.Environment.WebRootPath;
string contentPath = this.Environment.ContentRootPath;
return View();
}
}

By Using IWebHostEnvironment
In the below example, the IWebHostEnvironment is injected in the Controller and assigned to the private property Environment and later used to get the WebRootPath and ContentRootPath.
public class HomeController : Controller
{
private IWebHostEnvironment Environment;
public HomeController(IWebHostEnvironment _environment)
{
Environment = _environment;
}
public IActionResult Index()
{
string wwwPath = this.Environment.WebRootPath;
string contentPath = this.Environment.ContentRootPath;
return View();
}
}