private void RcvHeadData(IAsyncResult ar)
{
try {
PEPkg pack = (PEPkg)ar.AsyncState;
//返回的len为该次接受数据的总长度
int len = skt.EndReceive(ar);
if (len > 0)
{
//headIndex此时为数据的包括数据头和数据身体的总长度
pack.headIndex += len;
//如果数据的总长度得到的值要比数据头默认的4个字节要短，则说明该数据连数据头都不完整，继续接受数据直到数据完整
if (pack.headIndex < pack.headLen)
{
skt.BeginReceive(
pack.headBuff,
pack.headIndex,
pack.headLen - pack.headIndex,
SocketFlags.None,
new AsyncCallback(RcvHeadData),
pack);
}
else
{
//初始化数据身体，并且再次开始接受，这次接受的目的是按照数据头指定的长度接受数据身体
pack.InitBodyBuff();
skt.BeginReceive(pack.bodyBuff,
0,
pack.bodyLen,
SocketFlags.None,
new AsyncCallback(RcvBodyData),
pack);
}
}
//当len<=0的情况，即远程主机强制关闭了一个现有的连接，这时候服务器会疯狂接收到空数据，这时候就应该关闭掉这段Socket连接
else
{
//发送关闭连接的信息
OnDisConnected();
//关闭连接
Clear();
}
}
catch (Exception e)
{
PETool.LogMsg("RcvHeadError:" + e.Message, LogLevel.Error);
}
}
private void RcvHeadData(IAsyncResult ar)
{
try {
PEPkg pack = (PEPkg)ar.AsyncState;
if (skt.Available == 0)
{
OnDisConnected();
Clear();
return;
}
int len = skt.EndReceive(ar);
if (len > 0)
{
pack.headIndex += len;
if (pack.headIndex < pack.headLen)
{
skt.BeginReceive(
pack.headBuff,
pack.headIndex,
pack.headLen - pack.headIndex,
SocketFlags.None,
new AsyncCallback(RcvHeadData),
pack);
}
else
{
pack.InitBodyBuff();
skt.BeginReceive(pack.bodyBuff,
0,
pack.bodyLen,
SocketFlags.None,
new AsyncCallback(RcvBodyData),
pack);
}
}
else
{
OnDisConnected();
Clear();
}
}
catch (Exception e) {
PETool.LogMsg("RcvHeadError:" + e.Message, LogLevel.Error);
}
}
