public static async Task CopyToAsync(this Stream src, Stream target, long count, int bufferSize)
{
Validation.RequireValidBufferSize(bufferSize);
var bytesCopied = 0L;
var buffer = new byte[bufferSize];
while (bytesCopied < count)
{
var desiredBytesToCopy = (int)Math.Min(buffer.Length, count - bytesCopied);
var actualBytesToCopy = await src.ReadAsync(buffer, 0, desiredBytesToCopy);
if (actualBytesToCopy == 0)
{
throw new EndOfStreamException("Unexpected end of source stream");
}
await target.WriteAsync(buffer, 0, actualBytesToCopy);
bytesCopied += actualBytesToCopy;
}
}
public static async Task WriteAsync(this Stream stream, byte[] data, int bufferSize)
{
if (stream == null)
{
throw new ArgumentNullException(nameof(stream));
}
if (data == null)
{
throw new ArgumentNullException(nameof(data));
}
Validation.RequireValidBufferSize(bufferSize);
var bytesWritten = 0;
while (bytesWritten < data.Length)
{
var remain = data.Length - bytesWritten;
var bytesToWrite = Math.Min(remain, bufferSize);
await stream.WriteAsync(data, offset : bytesWritten, count : bytesToWrite);
bytesWritten += bytesToWrite;
}
}