Why the size of the directory is more then 79mb but in fact its about 19mb?

Why the size of the directory is more then 79mb but in fact its about 19mb?

s = Environment.GetEnvironmentVariable("UserProfile") + "\\Pictures";
string[] extensions = { "*.bmp", "*.jpg", "*.png", "*.gif"
};//add extensions you want to filter first
var photosfiles = extensions.SelectMany(x =>
Directory.GetFiles(s, x));
//string[] photosfiles = Directory.GetFiles(s, "*.*",
SearchOption.AllDirectories);
for (int i = 0; i < photosfiles.ToArray().Length; i++)
{
FileInfo fi = new FileInfo((photosfiles.ToArray()[i]));
DirectoryInfo d = new DirectoryInfo(tempphotos);
long dirSize = DirSize(d);
//if copying the file would take the directory over 50MB
then don't do it
if ((dirSize + fi.Length) <= 24117248)
fi.CopyTo(tempphotos + "\\" + fi.Name,true);
else
break;
}
What i changed is this :
string[] extensions = { "*.bmp", "*.jpg", "*.png", "*.gif" };//add
extensions you want to filter first
var photosfiles = extensions.SelectMany(x => Directory.GetFiles(s, x));
Before this two lines i had one line only:
string[] photosfiles = Directory.GetFiles(s, "*.*",
SearchOption.AllDirectories);
With this line it was working but after changed to the two lines above its
not working.
I had to change this lines and add now .ToArray()
for (int i = 0; i < photosfiles.ToArray().Length; i++)
{
FileInfo fi = new FileInfo((photosfiles.ToArray()[i]));
And then the result in the end is that
dirSize + fi.Length = 19526637 And fi.Length = 7916391
So its jumping right to the break.
When i used the first time only one line string[] photosfiles =
Directory.GetFiles(s, ".", SearchOption.AllDirectories);
And then without the .ToArray()
It was working good it was copying the files and then do the break;
Why now its not working after changed to this two lines and added the
.ToArray() ?