public class ReceiveDataBuffer{    private Memory<byte> items { get; set; } = Helper.EmptyArray.AsMemory();    private int size = 0;    public int Size    {        get        {            return size;        }        private set        {            if (value == 0)            {                items = Helper.EmptyArray;            }            else if (value > items.Length)            {                Memory<byte> newItems = new byte[value].AsMemory();                items.CopyTo(newItems);                items = newItems;            }        }    }    public Memory<byte> Data    {        get        {            return items;        }    }    public void AddRange(Memory<byte> data, int length)    {        BeResize(length);        data.Slice(0, length).CopyTo(items.Slice(size, length));        size += length;    }    public void AddRange(byte[] data, int offset, int length)    {        BeResize(length);        data.AsMemory(offset, length).CopyTo(items.Slice(size, length));        size += length;    }    public void RemoveRange(int index, int count)    {        if (index >= 0 && count > 0 && size - index >= count)        {            size -= count;            if (index < size)            {                items.Slice(index + count, size - index).CopyTo(items.Slice(index, size - index));            }        }    }    public void Clear(bool clearData = false)    {        size = 0;        if (clearData)        {            Size = 0;        }    }    private void BeResize(int length)    {        int _size = size + length;        if (_size > items.Length)        {            int newsize = items.Length * 2;            if (newsize < _size)            {                newsize = _size;            }            Size = newsize;        }    }}

ReceiveDataBuffer buffer = new ReceiveDataBuffer();byte[] bytes = new byte[8*1024];while(true){    //从网络接收到数据    int length =  socket.ReceiveAsync(bytes);    if (length == 0)    {        break;    }    //将网络数据添加到缓存中    buffer.AddRange(bytes, length);    do    {        //0-4字节是包长度内容        int packageLen = BitConverter.ToInt32(buffer.Data.Span);        if (packageLen > buffer.Size - 4)        {            break;        }                Memory<byte> data = buffer.Data.Slice(4, packageLen);        //拿data去随便干啥               //删除已使用的数据        buffer.RemoveRange(0, packageLen + 4);    } while (buffer.Size > 4);}