WinForms MouseWheel事件如何在F#中工作？

我想弄清楚mouseWheel事件在winforms库中是如何工作的.

虽然在谈到时没有任何好的例子可供学习 F#

我希望你们其中一个人能告诉我.

我在想这样的事情:

 onMouseWheelEvent =
      if MouseWheel event = scroll forward then
        printfn "zooming in"
      else 
        printfn "zooming out"

我知道这是我发布的一些愚蠢的代码,但我真的无法找到任何关于winforms mousewheelevent的东西,除了它存在.它的工作原理仍然是一个谜.

提前致谢.

尝试在f#interactive中运行它(由Tomas Petricek的fssnip上的类似示例提供):

open System.Windows.Forms

// Create form, label and add label to form
let form = new Form(Text = "Scroller Test")
let label = new Label()
form.Controls.Add(label)

// register mousewheel event handler and capture scrolling
form.MouseWheel.Add(fun e -> 
    match e.Delta with
    | n when n > 0 -> label.Text <- "Scrolled up"
    | n when n < 0 -> label.Text <- "Scrolled down"
    | _ -> ()) // making compiler happy even though e.Delta cannot be 0

// Show the form (in F# Interactive)
form.Show()