private async Task ProcessChat(AspNetWebSocketContext context)
{
WebSocket socket = context.WebSocket;
CancellationToken cancellationToken = new CancellationToken();
bool isExits = WebManager.AddUser(userKey, socket);
if (isExits == false)
{
//表示该用户有在线
await WebManager.SendToMySelf(cancellationToken, $"用户【{this.userKey}】 已在线", this.userKey);
}
else
{
//表示登录成功
//某人登陆后，给群里其他人发送提示信息(本人除外)
await WebManager.SendLoginSucesssNotice(cancellationToken, $"用户【{this.userKey}】 进入聊天室,当前时间：{DateTime.Now.ToYYYYMMDD()}");
while (socket.State == WebSocketState.Open)
{
ArraySegment <byte> buffer = new ArraySegment <byte>(new byte[2048]);
//接受指令
WebSocketReceiveResult result = await socket.ReceiveAsync(buffer, cancellationToken);
//表示是关闭指令
if (result.MessageType == WebSocketMessageType.Close)
{
//移除该用户对应的socket对象
WebManager.RemoveUser(userKey);
//发送离开提醒
await WebManager.SendOutNotice(cancellationToken, $"用户【{this.userKey}】 离开聊天室,当前时间：{DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss")}");
await socket.CloseAsync(WebSocketCloseStatus.NormalClosure, String.Empty, cancellationToken);
}
//获取是发送消息指令
else
{
string userMsg = Encoding.UTF8.GetString(buffer.Array, 0, result.Count);
//这里要区分是单发还是群发(通过与前端在内容开头做一个标记，来区分是单发还是群发)
if (userMsg.Length > 8 && userMsg.Substring(0, 8) == "$--$--**")
{
//表示是单发，截取内容和接受者的标记
var array = userMsg.Split(new string[] { "$--$--**" }, StringSplitOptions.None);
var receiveNotice = array[1];
string content = $"用户【{this.userKey}】 发来消息：{array[2]},当前时间：{DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss")}";
WebManager.SendSingleMessage(cancellationToken, content, receiveNotice);
}
else
{
//表示群发信息
string content = $"用户【{this.userKey}】 群发消息：{userMsg},当前时间：{DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss")}";
WebManager.SendAllMessage(cancellationToken, content, userKey);
}
}
}
}
}