问这两种对事件的订阅方式与在第二种情况下是否需要取消订阅之间的区别

EN

public event Action<Exception> Exception
{
    add => subscription.Exception += value;
    remove => subscription.Exception -= value;
}

// Subscribe
subscription.Data.Exception += PortfolioService_Exception;

// Unsubscribe
subscription.Data.Exception -= PortfolioService_Exception;

private void PortfolioService_Exception(Exception ex)
{
    _logger.LogInformation($"Error: {ex.StackTrace}");
}

subscription.Data.Exception += (ex) =>
{
    _logger.LogInformation($"Error: {ex.StackTrace}");
};

private async Task<bool> InitAsync()
{
    var restClient = new BinanceClient(new BinanceClientOptions
    {
        ApiCredentials = new ApiCredentials(ApiKey, SecretKey),
        AutoTimestamp = true,
        AutoTimestampRecalculationInterval = TimeSpan.FromMinutes(30),
        TradeRulesBehaviour = TradeRulesBehaviour.AutoComply,
#if DEBUG
        LogLevel = LogLevel.Debug,
        LogWriters = new List<ILogger> { _logger } // TODO: FIX
#endif
    });

    var socketClient = new BinanceSocketClient(new BinanceSocketClientOptions
    {
        ApiCredentials = new ApiCredentials(ApiKey, SecretKey),
        AutoReconnect = true,
        ReconnectInterval = TimeSpan.FromSeconds(15),
#if DEBUG
        LogLevel = LogLevel.Debug,
        LogWriters = new List<ILogger> { _logger } // TODO: FIX
#endif
    });
    
    var listenKeyResult = await restClient.Spot.UserStream.StartUserStreamAsync();
    if (!listenKeyResult.Success)
    {
        return false;
    }

    var subscription = await socketClient.Spot.SubscribeToUserDataUpdatesAsync(listenKeyResult.Data,
        null,
        null,
        data =>
        {
            // TODO: Fix the warning
            _logger.LogInformation($"ASD {data.Data.Balances}");
        },
        data =>
        {
            // TODO: Fix the warning
            _logger.LogInformation($"BALANCE DELTA {data.Data.BalanceDelta}");
        });

    if (!subscription.Success)
    {
        return false;
    }

    // Auto unsubscribe?
    subscription.Data.Exception += (ex) =>
    {
        _logger.LogInformation($"Error: {ex.StackTrace}");
    };

    // Subscribe
    subscription.Data.Exception += PortfolioService_Exception;

    // Unsubscribe
    subscription.Data.Exception -= PortfolioService_Exception;

    // TODO: Put a CancellationToken logic and `StopUserStreamAsync`. and subscription.Error -=
    var keepAliveTask = Task.Run(async () =>
    {
        while (true)
        {
            // Listen key is kept alive for 60 minutes.
            await restClient.Spot.UserStream.KeepAliveUserStreamAsync(listenKeyResult.Data);
            await Task.Delay(TimeSpan.FromMinutes(50));
        }
    });
    
    return true;
}

private void PortfolioService_Exception(Exception ex)
{
    _logger.LogInformation($"Error: {ex.StackTrace}");
}

using CryptoExchange.Net.Objects;
using System;
using System.Threading.Tasks;

namespace CryptoExchange.Net.Sockets
{
    /// <summary>
    /// Subscription to a data stream
    /// </summary>
    public class UpdateSubscription
    {
        private readonly SocketConnection connection;
        private readonly SocketSubscription subscription;

        /// <summary>
        /// Event when the connection is lost. The socket will automatically reconnect when possible.
        /// </summary>
        public event Action ConnectionLost
        {
            add => connection.ConnectionLost += value;
            remove => connection.ConnectionLost -= value;
        }

        /// <summary>
        /// Event when the connection is closed. This event happens when reconnecting/resubscribing has failed too often based on the <see cref="SocketClientOptions.MaxReconnectTries"/> and <see cref="SocketClientOptions.MaxResubscribeTries"/> options,
        /// or <see cref="SocketClientOptions.AutoReconnect"/> is false
        /// </summary>
        public event Action ConnectionClosed
        {
            add => connection.ConnectionClosed += value;
            remove => connection.ConnectionClosed -= value;
        }

        /// <summary>
        /// Event when the connection is restored. Timespan parameter indicates the time the socket has been offline for before reconnecting. 
        /// Note that when the executing code is suspended and resumed at a later period (for example laptop going to sleep) the disconnect time will be incorrect as the diconnect
        /// will only be detected after resuming. This will lead to an incorrect disconnected timespan.
        /// </summary>
        public event Action<TimeSpan> ConnectionRestored
        {
            add => connection.ConnectionRestored += value;
            remove => connection.ConnectionRestored -= value;
        }

        /// <summary>
        /// Event when the connection to the server is paused based on a server indication. No operations can be performed while paused
        /// </summary>
        public event Action ActivityPaused
        {
            add => connection.ActivityPaused += value;
            remove => connection.ActivityPaused -= value;
        }

        /// <summary>
        /// Event when the connection to the server is unpaused after being paused
        /// </summary>
        public event Action ActivityUnpaused
        {
            add => connection.ActivityUnpaused += value;
            remove => connection.ActivityUnpaused -= value;
        }

        /// <summary>
        /// Event when an exception happens during the handling of the data
        /// </summary>
        public event Action<Exception> Exception
        {
            add => subscription.Exception += value;
            remove => subscription.Exception -= value;
        }

        /// <summary>
        /// The id of the socket
        /// </summary>
        public int SocketId => connection.Socket.Id;

        /// <summary>
        /// The id of the subscription
        /// </summary>
        public int Id => subscription.Id;

        /// <summary>
        /// ctor
        /// </summary>
        /// <param name="connection">The socket connection the subscription is on</param>
        /// <param name="subscription">The subscription</param>
        public UpdateSubscription(SocketConnection connection, SocketSubscription subscription)
        {
            this.connection = connection;
            this.subscription = subscription;
        }
        
        /// <summary>
        /// Close the subscription
        /// </summary>
        /// <returns></returns>
        public Task CloseAsync()
        {
            return connection.CloseAsync(subscription);
        }

        /// <summary>
        /// Close the socket to cause a reconnect
        /// </summary>
        /// <returns></returns>
        internal Task ReconnectAsync()
        {
            return connection.Socket.CloseAsync();
        }

        /// <summary>
        /// Unsubscribe a subscription
        /// </summary>
        /// <returns></returns>
        internal async Task UnsubscribeAsync()
        {
            await connection.UnsubscribeAsync(subscription).ConfigureAwait(false);
        }

        /// <summary>
        /// Resubscribe this subscription
        /// </summary>
        /// <returns></returns>
        internal async Task<CallResult<bool>> ResubscribeAsync()
        {
            return await connection.ResubscribeAsync(subscription).ConfigureAwait(false);
        }
    }
}