什么是F＃等效于C＃“public event” [英] What is F# equivalent of C# "public event "

问题描述

我想从这篇文章翻译为F＃代码 http://www.codeproject.com/Articles/35532/C-COM-Object-for-Use-In-JavaScript-HTML-包括

我偶然发现了这一行：

  public委托void MyFirstEventHandler（string args）; 
 public event MyFirstEventHandler MyFirstEvent; 
  

我试图在F＃中翻译为：

  type MyFirstEventHandler = delegate of string  - >单元
类型MyFsComComponent（）= 
 let my_event = new Event< MyFirstEventHandler，string> （）
 
 [< CLIEvent>] 
 member x.MyFirstEvent = my_event.Publish 
  

我得到：'MyFirstEventHandler'有一个非标准的委托

我可以编译：

  type MyFirstEventHandler = delegate of obj * string  - >单位
  

但这不是COM控制中需要的。

此问题也出现在 F＃类作弊页中 - public event仍然没有解决方案

已解决。感谢Leaf Garland

  type MyFirstEventHandler = delegate of string  - >单元
类型MyFsComComponent（）= 
 let my_event = new DelegateEvent< MyFirstEventHandler> （）
 
 [< CLIEvent>] 
 member x.MyFirstEvent = my_event.Publish 
  

com / en-us / library / dd233189.aspx> F＃事件类期望参数类型作为通用参数，而不是委托类型。它还期望委托是一个标准类型（例如 obj * eventargs-> unit ）。对于任意委托，使用DelegateEvent。

  type MyFirstEventHandler = delegate of string  - > unit 
 type MyFsComComponent（）= 
 let my_event = new DelegateEvent< MyFirstEventHandler>（）
 
 [< CLIEvent>] 
 member x.MyFirstEvent = my_event.Publish 
  

I'm trying to translate to F# code from this article http://www.codeproject.com/Articles/35532/C-COM-Object-for-Use-In-JavaScript-HTML-Including

I've stumbled on this lines:

public delegate void MyFirstEventHandler(string args);
public event MyFirstEventHandler MyFirstEvent;

I've tried to translate this in F# as:

type MyFirstEventHandler = delegate of string -> unit
type MyFsComComponent () = 
    let my_event = new Event<MyFirstEventHandler,string> ()

    [<CLIEvent>]
    member x.MyFirstEvent = my_event.Publish

And I get: 'MyFirstEventHandler' has a non-standard delegate

I can compile with:

type MyFirstEventHandler = delegate of obj*string -> unit

But this is not what needed in COM-control.

This question is also raised in F# classes cheat sheet - "public event" still did not have solution

SOLVED. Thanks to Leaf Garland

type MyFirstEventHandler = delegate of string -> unit
type MyFsComComponent () =    
    let my_event = new DelegateEvent<MyFirstEventHandler> ()

    [<CLIEvent>]
    member x.MyFirstEvent = my_event.Publish

does the trick.

解决方案

The F# Event class expects the argument types as generic parameters, not the delegate type. It also expects that the delegate is a standard type (e.g. something like obj*eventargs->unit). For arbitrary delegates use DelegateEvent.

type MyFirstEventHandler = delegate of string -> unit
type MyFsComComponent () = 
    let my_event = new DelegateEvent<MyFirstEventHandler>()

    [<CLIEvent>]
    member x.MyFirstEvent = my_event.Publish

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