C# RNGCryptoServiceProvider GetBytes(large byte array) vs looping GetBytes(1 byte)

Question

I was wondering if there's a difference in security between the following:

CASE A:

byte[] data = new byte[47];
using(RNGCryptoServiceProvider crypto = new RNGCryptoServiceProvider())
{
    crypto.GetBytes(data);
}

CASE B:

byte[] data = new byte[47];
using(RNGCryptoServiceProvider crypto = new RNGCryptoServiceProvider())
{
    for(int i = 0; i < 47; i++)
    {
        byte[] byte = new byte[1];
        crypto.GetBytes(byte);
        data[i] = byte;       
    }
}

I was wondering because I was inspired by the example of MSDN. Which basically checks whether the byte received was fair due to the unfair distribution of using modulo on a limited value. (I was building a random string generator and I don't want to give the characters early in the alphabet the advantage of an unfair distribution)

So basically my question is, is there a difference in security whether I loop "GetBytes" to get N bytes (case b), or use "GetBytes" directly to get N bytes (case a).

Thank you for your time

Answer 1

No, there isn't. The bytes are generated the same way no matter whichever way you get them.