如何从我的数据库获取用户id并使用ASP.NET核心MVC显示它？

using Microsoft.AspNetCore.Mvc;
using System.Data.SqlClient;

public class UserController : Controller
{
    public IActionResult ShowUserId()
    {
        string connectionString = "YourConnectionString"; // 替换为你的数据库连接字符串

        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            connection.Open();

            string query = "SELECT UserId FROM Users"; // 替换为你的查询语句

            using (SqlCommand command = new SqlCommand(query, connection))
            {
                using (SqlDataReader reader = command.ExecuteReader())
                {
                    if (reader.Read())
                    {
                        int userId = reader.GetInt32(0); // 假设用户id在第一列

                        ViewBag.UserId = userId; // 将用户id存储在ViewBag中，以便在视图中访问
                    }
                }
            }
        }

        return View();
    }
}

@{
    ViewData["Title"] = "User ID";
}

<h1>User ID: @ViewBag.UserId</h1>