public void Base64BytesEncodeTest(int count)
{
var inputBytes = new byte[count];
var r = new Random(count);
r.NextBytes(inputBytes);
var expectedBase64String = Convert.ToBase64String(inputBytes);
var expectedBase64Buffer = expectedBase64String.ToCharArray().Select(v => (byte)v).ToArray();
// transform block
var inputOffset = r.Next(0, 100);
var inputBuffer = new byte[inputOffset + inputBytes.Length + inputOffset];
Buffer.BlockCopy(inputBytes, 0, inputBuffer, inputOffset, inputBytes.Length);
var outputOffset = r.Next(0, 100);
var outputBuffer = new byte[outputOffset + expectedBase64Buffer.Length];
var written = Base64Convert.Encode(new ArraySegment <byte>(inputBuffer, inputOffset, inputBytes.Length), new ArraySegment <byte>(outputBuffer, outputOffset, outputBuffer.Length - outputOffset), out var inputUsed, out var outputUsed);
var actualOutput = outputBuffer.Skip(outputOffset).ToArray();
Assert.Equal(expectedBase64Buffer.Length, Base64Convert.GetBase64OutputLength(inputBytes.Length, true));
Assert.Equal(expectedBase64Buffer.Length, written);
Assert.Equal(expectedBase64Buffer.Length, outputUsed);
Assert.Equal(inputBytes.Length, inputUsed);
Assert.Equal(expectedBase64Buffer, actualOutput);
}
