当用户点击反应时，我无法发布角色

Question

如您所见，如果您删除了发布代码的位置，当用户点击反应时，它会被计分并以用户名的形式作为响应出现。因为我在程序中编写了这个方法并添加了遗留的 ModuleBase 它是有限的，我将不得不返回 null，我总是将这个问题像素化，只是 dobavlyu 在所需类的参数中，但现在我不能添加超过 3 个类因为字段 ReactionAdded 需要 3 个参数，对于反应，告诉我方法内部如何获取类 SocketGuild、SocketGuildUser 和 Yes 角色变量返回 Null 因为 ModuleBase

 [Command("react")]
        public async Task HandleReaction()
        {
            RestUserMessage message = await Context.Channel.SendMessageAsync("react");
            Program.MessageId = message.Id;
        }

internal static ulong MessageId { get; set; }
  public  ITextChannel textChannel;

    public SocketGuildUser user;    

private async Task OnReactionAdd(Cacheable<IUserMessage, ulong> cache, ISocketMessageChannel channel, SocketReaction reaction)
        {
          
            if (reaction.MessageId == Program.MessageId)
            {
                  if (reaction.Emote.Name == "????")
            {
                

                ulong roleid = 747992707351183541;
                var role = textChannel.Guild.GetRole(roleid); //System.NullReferenceException: "Object reference not set to an instance of an object."

                await user.AddRoleAsync(role);
                await channel.SendMessageAsync(reaction.User.Value.Username);
            }
            }
        }

Answer 1

private async Task OnReactionAdd(Cacheable<IUserMessage, ulong> cache, ISocketMessageChannel channel, SocketReaction reaction)
{  
    if (reaction.MessageId == Program.MessageId)
    {
        if (reaction.Emote.Name == "?")
        {
            ulong roleid = 747992707351183541;
            //here can cast the ISocketMessageChannel to an ITextChannel
            if (channel is SocketTextChannel textChannel) 
            {
                var role = textChannel.Guild.GetRole(roleid); 
                var user = textChannel.Guild.GetUser(reaction.UserId);
                
                await user.AddRoleAsync(role);
                await textChannel.SendMessageAsync(user.Username);
            }   
        }
    }    
}