定义 TypeScript 回调类型 [英] Defining TypeScript callback type

问题描述

我在 TypeScript 中有以下类:

I've got the following class in TypeScript:

class CallbackTest
{
    public myCallback;

    public doWork(): void
    {
        //doing some work...
        this.myCallback(); //calling callback
    }
}

我正在使用这样的类:

var test = new CallbackTest();
test.myCallback = () => alert("done");
test.doWork();

代码有效，所以它按预期显示了一个消息框.

The code works, so it displays a messagebox as expected.

我的问题是:我可以为我的类字段 myCallback 提供任何类型吗?现在，公共字段 myCallback 的类型为 any，如上所示.如何定义回调的方法签名?或者我可以将类型设置为某种回调类型吗?或者我可以做这些吗?我是否必须使用 any(隐式/显式)?

My question is: Is there any type I can provide for my class field myCallback? Right now, the public field myCallback is of type any as shown above. How can I define the method signature of the callback? Or can I just set the type to some kind of callback-type? Or can I do nether of these? Do I have to use any (implicit/explicit)?

我尝试过类似的方法，但没有奏效(编译时错误):

I tried something like this, but it did not work (compile-time error):

public myCallback: ();
// or:
public myCallback: function;

我在网上找不到对此的任何解释，所以希望您能帮助我.

I couldn't find any explanation to this online, so I hope you can help me.

推荐答案

我刚刚在 TypeScript 语言规范中找到了一些东西，它相当简单.我非常接近.

I just found something in the TypeScript language specification, it's fairly easy. I was pretty close.

语法如下:

public myCallback: (name: type) => returntype;

在我的例子中，它是

class CallbackTest
{
    public myCallback: () => void;

    public doWork(): void
    {
        //doing some work...
        this.myCallback(); //calling callback
    }
}

作为类型别名:

type MyCallback = (name: type) => returntype;

这篇关于定义 TypeScript 回调类型的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！