如何在TypeScript中指定任何新的类型?

时间:2015-10-19 21:14:45

标签: typescript method-signature newable

我试过这个,但它没有用。 Foo只是对有效的测试。 Bar是真正的尝试,它应该接收任何新的类型,但Object的子类不能用于此目的。

class A {

}
class B {
    public Foo(newable: typeof A):void {

    }
    public Bar(newable: typeof Object):void {

    }
}

var b = new B();
b.Foo(A);
b.Bar(A); // <- error here

2 个答案:

答案 0 :(得分:9)

您可以使用{ new(...args: any[]): any; }来允许任何具有任何参数的构造函数的对象。

class A {

}

class B {
    public Foo(newable: typeof A):void {

    }

    public Bar(newable: { new(...args: any[]): any; }):void {

    }
}

var b = new B();
b.Foo(A);
b.Bar(A);  // no error
b.Bar({}); // error

答案 1 :(得分:0)

如果您只想强制某些新事物,则可以指定构造函数的返回类型

interface Newable {
  errorConstructor: new(...args: any) => Error; // <- put here whatever Base Class you want
}

等效

declare class AnyError extends Error { // <- put here whatever Base Class you want
  // constructor(...args: any) // you can reuse or override Base Class' contructor signature
}

interface Newable {
  errorConstructor: typeof AnyError;
}

测试

class NotError {}
class MyError extends Error {}

const errorCreator1: Newable = {
  errorConstructor: NotError, // Type 'typeof NotError' is missing the following properties from type 'typeof AnyError': captureStackTrace, stackTraceLimitts
};

const errorCreator2: Newable = {
  errorConstructor: MyError, // OK
};