/// <summary>
/// 软删除连接信息
/// </summary>
/// <param name="roomId">房间ID</param>
/// <param name="userId">用户ID</param>
/// <returns>表示软删除连接的任务</returns>
public async Task <string> PerformSoftDeleteOfConnectionAsync(int roomId, int userId)
{
var connection = await _dbContext.Connection.FindAsync(roomId, userId);
// 如果用户打开了两个窗口，这里会出问题
if (connection == null)
{
return(string.Empty);
}
connection.IsDeleted = true;
_dbContext.Update(connection);
await _dbContext.SaveChangesAsync();
// 返回空字符串避免前台出错
return(string.Empty);
}
/// <summary>
/// 加入房间
/// </summary>
/// <param name="roomHashid">房间哈希ID</param>
/// <returns>表示加入房间的任务，返回房间名和加入该房间的时间</returns>
public async Task <ChatRoomInitialDisplayDto> JoinRoomAsync(string roomHashid)
{
var roomId = HashidsHelper.Decode(roomHashid);
var userId = HashidsHelper.Decode(Context.User.FindFirst("uid").Value);
var username = HttpUtility.UrlDecode(Context.User.Identity.Name);
// 因为用户可能会尝试用一个账号同时登陆两个房间
// 这里查询条件不加上房间ID，前一个房间内的用户会被提示在别处登录
var connection = await _dbContext.Connection
.FirstOrDefaultAsync(x => x.UserId == userId);
string msgId = null;
string connIdToBeRemoved = null;
if (connection == null)
{
// 第一次进入该房间
msgId = "I001";
_dbContext.Add(new Connection
{
RoomId = roomId,
UserId = userId,
Username = username,
ConnectionId = Context.ConnectionId
});
}
else
{
// 如果用户同时打开两个窗口
if (connection.IsOnline.Value)
{
connIdToBeRemoved = connection.ConnectionId;
}
// 重连的情况下
msgId = "I003";
connection.IsOnline = true;
connection.ConnectionId = Context.ConnectionId;
// 只保留一条记录
_dbContext.Update(connection);
}
await _dbContext.SaveChangesAsync();
// 将用户添加到分组
await Groups.AddAsync(Context.ConnectionId, roomHashid);
// 只加载加入房间前的消息，避免消息重复显示
long unixTimeMilliseconds = new DateTimeOffset(DateTime.Now).ToUnixTimeMilliseconds();
// 显示欢迎用户加入房间的消息
await Clients.Group(roomHashid).InvokeAsync(
"receiveSystemMessage",
_msg.GetMessage(msgId, username));
if (!string.IsNullOrEmpty(connIdToBeRemoved))
{
// 前一个窗口显示消息，告知账号已经在其他地方登陆
await Clients.Client(connIdToBeRemoved).InvokeAsync("onDuplicateLogin");
await Groups.RemoveAsync(connIdToBeRemoved, roomHashid);
}
// 显示用户列表
await RefreshMemberListAsync(roomHashid, roomId);
var room = await _dbContext.ChatRoom
.Where(r => r.Id == roomId)
.Select(r => new { r.Name, r.OwnerId })
.FirstOrDefaultAsync();
return(new ChatRoomInitialDisplayDto
{
OwnerId = HashidsHelper.Encode(room.OwnerId),
RoomName = room.Name,
EntryTime = unixTimeMilliseconds
});
}