Question

Basically I’m reading all the bytes from a file into a byte array using stream reader.

The array I have declared looks like this : byte[] array = new byte[256];

The size of the array 256 can read the whole bytes from the file? Saying that a file has 500 bytes instead of 256?

Or the each element from the array has the size 256 bytes?

Answer 1

You could use File.ReadAllBytes instead:

byte[] fileBytes = File.ReadAllBytes(path);

or if you just want to know the size, with a FileInfo object:

FileInfo f = new FileInfo(path);
long s1 = f.Length;

Edit: If you want to it “in a classical way” as commented:

byte[] array;
using (FileStream fileStream = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read))
{
    int num = 0;
    long length = fileStream.Length;
    if (length > 2147483647L)
    {
        throw new ArgumentException("File is greater than 2GB, hence it is too large!", "path");
    }
    int i = (int)length;
    array = new byte[i];
    while (i > 0)
    {
        int num2 = fileStream.Read(array, num, i);
        num += num2;
        i -= num2;
    }
}

(reflected via ILSpy)