Typescript如何声明子类类型？

Question

有可能有这样的东西吗？

export abstract class FilterBoxElement {
    abstract getEntities: any;
}
export interface FilterBoxControlSuggestions extends FilterBoxElement {
    getEntities: // some implementation with different parameters
}
export interface FilterBoxControlDropDown extends FilterBoxElement {
    getEntities: // some implementation with different parameters
}

export interface FilterBoxDataProps {
    controlElement: FilterBoxElement // FilterBoxControlSuggestions or FilterBoxControlDropDown 
}

我希望那controlElement必须是一个FilterBoxControlSuggestions或一个FilterBoxControlDropDown.但是现在我可以把所有东西放进去.有没有办法实现这个目标？

Answer 1

您可以使用联合类型执行此操作:

export interface FilterBoxDataProps {
    controlElement: FilterBoxControlSuggestions | FilterBoxControlDropDown 
}

或者如果你想要FilterBoxElement的所有子类,那么使用泛型:

export interface FilterBoxDataProps<T extends FilterBoxElement> {
    controlElement: T
}