如何使泛型類型約束變得不可思議

Question

我有這兩個代碼片段，如何更改它們，以便MemberModel可以作為泛型類型傳遞並保持可實例化，以便可以將follow方法提取到其自己的導出函數中？

export interface IFollowable {
    follow(user: IUserModel): IMemberModel;
}

export class CardModel implements ICardModel, IFollowable {
    public follow(user: IUserModel): IMemberModel {
        let member = new MemberModel({userId: user.id});
        member.role = UserRoles.follower;
        this.members.push(member);
        return member;
    }
}

我該如何進行關注和IFollowable泛型，以便我傳遞的任何類型都像MemberModel這樣保持可更新狀態？

Answer 1

這樣我傳遞的任何類型都可以像MemberModel一樣保持新狀態

由於打字稿泛型在編譯時會被刪除，因此您需要顯式傳遞它們，例如使用如下所示的工廠：

type User = {name:string};
type Member = {name: string};
type MemberCreator = {new (user:User): Member};

interface Followable {
    follow(user: User, memberCreator: MemberCreator): Member;
}

export class CardModel implements Followable {
    public follow(user: User, memberCreator: MemberCreator): Member {
       return new memberCreator(user);
    }
}