bool success = GetDiskFreeSpaceEx("C:\\", out FreeBytesAvailable, out TotalNumberOfBytes,
out TotalNumberOfFreeBytes);
if (!success)
throw new System.ComponentModel.Win32Exception();
Console.WriteLine("Free Bytes Available: {0,15:D}", FreeBytesAvailable);
Console.WriteLine("Total Number Of Bytes: {0,15:D}", TotalNumberOfBytes);
Console.WriteLine("Total Number Of FreeBytes: {0,15:D}", TotalNumberOfFreeBytes);