/// <summary>
/// 人对人聊天 连接服务器
/// </summary>
/// <param name="sendid">发送人</param>
/// <param name="receiveid">接收人</param>
/// <returns></returns>
public Task ClientToClient(string sendid, string receiveid)
{
if (sendid == null || receiveid == null)
{
throw new ArgumentNullException("sendid or receiveid can't be null");
}
//获取组名
string groupName = MessageUtils.GetGroupName(sendid, receiveid);
//将当前用户添加到此组织内
Groups.Add(CurrentUserConnectionId, groupName);
//构建系统连接成功消息
//读取历史记录 --- 2016-3-7 修改
var historyMsg = MessageUtils.GetHistoryMessage(sendid, receiveid);
var msg = MessageUtils.GetSystemMessage(groupName, MessageConfig.ClientToClientConnectedSucceed, new { t = MessageConfig.ClientTypeCTC, currentid = sendid, receiveid = receiveid, history = historyMsg });
//将消息推送到当前组 （A和B聊天的组） 同样调用receiveMessage方法
return(Clients.Caller.receiveMessage(msg));
}