如何在F#中使用winforms创建模拟时钟？

open System
open System.Windows.Forms
open System.Drawing

// 创建一个继承自Form的窗体类
type ClockForm() as this =
    inherit Form()

    // 创建一个Timer控件用于更新时钟
    let timer = new Timer()

    // 重写OnLoad方法，在窗体加载时启动计时器
    override this.OnLoad(e: EventArgs) =
        base.OnLoad(e)
        timer.Interval <- 1000 // 设置计时器间隔为1秒
        timer.Tick.Add(fun _ -> this.Invalidate()) // 每秒触发一次Tick事件
        timer.Start() // 启动计时器

    // 重写OnPaint方法，在窗体绘制时绘制时钟
    override this.OnPaint(e: PaintEventArgs) =
        let g = e.Graphics
        let now = DateTime.Now
        let timeString = sprintf "%02d:%02d:%02d" now.Hour now.Minute now.Second
        let font = new Font("Arial", 24.0f)
        let brush = new SolidBrush(Color.Black)
        g.DrawString(timeString, font, brush, PointF(10.0f, 10.0f)) |> ignore

// 创建一个ClockForm实例并运行应用程序
[<EntryPoint>]
let main argv =
    let form = new ClockForm()
    Application.Run(form)
    0