/// <summary>
/// Reads bytes from current stream and writes them to another stream.
/// </summary>
/// <param name="source">The source stream.</param>
/// <param name="destination">The destination stream.</param>
/// <param name="count">The number of bytes to copy.</param>
/// <param name="bufferSize">The size of the buffer. This value must be
/// greater than zero. The default size is 1048576.</param>
/// <returns>The number of bytes copied.</returns>
/// <exception cref="ArgumentNullException"><paramref name="destination"/> or
/// <paramref name="source"/> is <see langword="null"/></exception>
/// <exception cref="NotSupportedException">When <paramref name="source"/> cannot be read or <paramref name="destination"/> cannot be written.</exception>
public static long CopyTo(this Stream source, Stream destination, long count, int bufferSize = 1048576)
{
if (source == null)
{
throw new ArgumentNullException(nameof(source));
}
if (destination == null)
{
throw new ArgumentNullException(nameof(destination));
}
if (!source.CanRead)
{
throw new NotSupportedException("The current stream does not support reading.");
}
if (!destination.CanWrite)
{
throw new NotSupportedException("The destination does not support writing.");
}
byte[] buffer = ArrayPool <byte> .GetT(bufferSize);
long copied = 0;
int readed;
bufferSize = (int)Math.Min(buffer.Length, count);
while (copied < count && (readed = source.Read(buffer, 0, bufferSize)) != 0)
{
copied += readed;
destination.Write(buffer, 0, readed);
}
return(copied);
}
public static void Set <T>(ref T[] array, ref int length, ReadOnlySpan <T> value) where T : unmanaged
{
if (array == null || !(value.Length <= array.Length))
{
if (array != null && array.Length > 0)
{
ArrayPool <T> .Return(array);
}
array = ArrayPool <T> .GetT(value.Length);
}
length = value.Length;
MemUtil.Copy(array, value);
}
public static void SetManaged <T>(ref T[] array, ref int length, ReadOnlySpan <T> value)
{
if (value == default || value.Length == 0)
{
array = Array.Empty <T>();
length = 0;
return;
}
if (!(value.Length <= array.Length))
{
ArrayPool <T> .Return(array);
array = ArrayPool <T> .GetT(value.Length);
}
length = value.Length;
for (int i = 0; i < value.Length; i++)
{
array[i] = value[i];
}
}
