ASP.NET MVC使用Dapper管理SQLConnection

public class HomeController : Controller
{
    SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings[\"ajh\"].ConnectionString);

    public HomeController()
    {
    }

    public ActionResult Index()
    {
        // get me all comments
        conn.Open();
        var comments = conn.ExecuteMapperQuery<Comment>(\"select * from Comment\");
        conn.Close();

        return View(comments);
    }
}

public class HomeController : Controller
{
    public HomeController()
    {
    }

    public ActionResult Index()
    {
        List<Comment> comments;
        using (var conn = new SqlConnection(/* ... */))
        {
            conn.Open();
            comments = conn.ExecuteMapperQuery<Comment>(\"select * from Comment\");
        }
        return View(comments);
    }
}

.ExecuteMapperQuery