/// <summary>
/// 查找一个完整的消息，如果不符合条件，则返回空，否则返回一个完整的消息
/// </summary>
/// <param name="readBuffer">标本从流中读取的缓冲数组</param>
/// <param name="rest">查找到一个完整的消息后，剩余未处理的数组长度，查找不到完整消息时为0</param>
/// <returns></returns>
public byte[] Filter(List <byte> readBuffer, out int rest)
{
int beginIndex = 0;
int endIndex = 0;
byte[] receive = null;
if (HasReceivedData)
{
//如果已接收过数据，则应先从0开始找结束标志
//如果有，则返回处理
endIndex = FindEndIndex(readBuffer, -1);//-1表示从开始0开始查找
if (endIndex >= 0)
{
ByteReceived.AddRange(readBuffer.Take(endIndex + m_endMark.Length));
//此时一个消息已接收完整，则返回处理
rest = readBuffer.Count - (endIndex + m_endMark.Length);
receive = ByteReceived.ToArray();
return(receive);
}
else
{
ByteReceived.AddRange(readBuffer);
NextReceiveDataFilter = this;
rest = 0;
return(null);
}
}
beginIndex = FindStartIndex(readBuffer);
if (beginIndex == -1)
{
//如果没有开始标记，则判断是否已接收过数据
//如果已接收过数据，再判断是否有结束标志，
// 如果有结束标志，则将结束标志前的数据添加到已接收数据，
// 如果没有结束标志，则将整个缓冲数组添加到已接收数据；
//如果没有开始标记，又未接收过数据，则丢弃该段数据
if (HasReceivedData)
{
endIndex = FindEndIndex(readBuffer, beginIndex);
if (endIndex >= 0)
{
ByteReceived.AddRange(readBuffer.Take(endIndex + m_endMark.Length));
//此时一个消息已接收完整，则返回处理
rest = readBuffer.Count - (endIndex + m_endMark.Length);
receive = ByteReceived.ToArray();
return(receive);
}
else
{
ByteReceived.AddRange(readBuffer);
NextReceiveDataFilter = this;
rest = 0;
return(null);
}
}
else
{
rest = 0;
Reset();
//如果有异常，可能是接收的数据不符合通信协议，记录日志
Log("Received data: " + System.Text.Encoding.Default.GetString(readBuffer.ToArray()));
return(null);
}
}
endIndex = FindEndIndex(readBuffer, beginIndex);
if (endIndex == -1)
{
//如果有开始标志，没有结束标记，则将开始标志后面的数据添加到已接收数据
ByteReceived = new List <byte>();
ByteReceived.AddRange(readBuffer.Skip(beginIndex).ToList());
NextReceiveDataFilter = this;
HasReceivedData = true;
rest = 0;
return(null);
}
else
{
//如果有开始和结束标志，则说明是一个完整的消息，则直接返回处理
List <byte> temp = readBuffer.Take(endIndex + m_endMark.Length).ToList(); //先获取结束标志前的所有数据
temp = temp.Skip(beginIndex).ToList(); //再从开始位置取后面所有数据
ByteReceived = new List <byte>();
ByteReceived.AddRange(temp);
//此时一个消息已接收完整，则返回处理
rest = readBuffer.Count - (endIndex + m_endMark.Length);
receive = ByteReceived.ToArray();
return(receive);
}
}
/// <summary>
/// 查找一个完整的消息，如果不符合条件，则返回空，否则返回一个完整的消息
/// </summary>
/// <param name="readBuffer">标本从流中读取的缓冲数组</param>
/// <param name="rest">查找到一个完整的消息后，剩余未处理的数组长度，查找不到完整消息时为0</param>
/// <returns></returns>
public byte[] Filter(List <byte> readBuffer, out int rest)
{
int beginIndex = 0;
byte[] receive = null;
if (HasReceivedData)
{
if (m_dataLen > 0)
{
//表示开头已经接收了消息长度，判断消息长度是否足够即可
List <byte> bufferAfterBegin = new List <byte>();
bufferAfterBegin.AddRange(ByteReceived);
bufferAfterBegin.AddRange(readBuffer);
if (bufferAfterBegin.Count >= m_dataLen)
{
ByteReceived.AddRange(bufferAfterBegin.Take(m_dataLen));
if (CheckVerifyCode(ByteReceived))
{
rest = bufferAfterBegin.Count - m_dataLen;
receive = ByteReceived.ToArray();
return(receive);
}
else
{
rest = bufferAfterBegin.Count - m_dataLen;
Reset();
return(null);
}
}
else
{
ByteReceived.AddRange(bufferAfterBegin);
NextReceiveDataFilter = this;
rest = 0;
return(null);
}
}
else
{
List <byte> bufferAfterBegin = new List <byte>();
bufferAfterBegin.AddRange(ByteReceived);
bufferAfterBegin.AddRange(readBuffer);
if (bufferAfterBegin.Count > (m_beginMark.Length + m_dataLenByteCount))
{
//获取数据长度的值
byte[] dataLenByteArray = bufferAfterBegin.Take(m_beginMark.Length + m_dataLenByteCount).ToArray();
dataLenByteArray = dataLenByteArray.Skip(m_beginMark.Length).ToArray();
m_dataLen = BitConverter.ToInt32(dataLenByteArray.Reverse().ToArray(), 0);
//计算是否接收了完整消息
if (bufferAfterBegin.Count >= m_dataLen)
{
ByteReceived.AddRange(bufferAfterBegin.Take(m_dataLen));
if (CheckVerifyCode(ByteReceived))
{
rest = bufferAfterBegin.Count - m_dataLen;
receive = ByteReceived.ToArray();
return(receive);
}
else
{
rest = bufferAfterBegin.Count - m_dataLen;
Reset();
return(null);
}
}
else
{
ByteReceived.AddRange(bufferAfterBegin);
NextReceiveDataFilter = this;
rest = 0;
return(null);
}
}
else
{
ByteReceived.AddRange(bufferAfterBegin);
NextReceiveDataFilter = this;
rest = 0;
return(null);
}
}
}
beginIndex = FindStartIndex(readBuffer);
if (beginIndex == -1)
{
rest = 0;
Reset();
//如果有异常，可能是接收的数据不符合通信协议，记录日志
Log("Received data: " + System.Text.Encoding.Default.GetString(readBuffer.ToArray()));
return(null);
}
else
{
//获取数据长度
//开始标志后的数据长度如果足够长（开始标志长度+数据长度开始位置+数据长度字节数），
//则获取数据长度信息，如果不够长，则继续接收数据
List <byte> bufferAfterBegin = readBuffer.Skip(beginIndex).ToList();
if (bufferAfterBegin.Count > (m_beginMark.Length + m_dataLenByteCount))
{
//获取数据长度的值
byte[] dataLenByteArray = bufferAfterBegin.Take(m_beginMark.Length + m_dataLenByteCount).ToArray();
dataLenByteArray = dataLenByteArray.Skip(m_beginMark.Length).ToArray();
m_dataLen = BitConverter.ToInt32(dataLenByteArray.Reverse().ToArray(), 0);
ByteReceived = new List <byte>();
//计算是否接收了完整消息
if (bufferAfterBegin.Count >= m_dataLen)
{
ByteReceived.AddRange(bufferAfterBegin.Take(m_dataLen));
if (CheckVerifyCode(ByteReceived))
{
rest = bufferAfterBegin.Count - m_dataLen;
receive = ByteReceived.ToArray();
return(receive);
}
else
{
rest = bufferAfterBegin.Count - m_dataLen;
Reset();
return(null);
}
}
else
{
ByteReceived.AddRange(bufferAfterBegin);
NextReceiveDataFilter = this;
rest = 0;
return(null);
}
}
else
{
ByteReceived = new List <byte>();
ByteReceived.AddRange(bufferAfterBegin);
NextReceiveDataFilter = this;
rest = 0;
return(null);
}
}
}