• 只会比较 实例成员

class Person {
    public name: string;
}

class Animal {
    public name: string;
}

let p: Person;
let a: Animal;
p = a;
a = p;

• 只能将 多 的属性赋值给 少 的，不可将 少 的属性赋值给 多 的

class Person {
    public name: string;
    public age: number;
}

class Animal {
    public name: string;
}

let p: Person;
let a: Animal;

// 多????少
a = p;

// 少????多
p = a;

• 不会比较类的 构造函数 和 静态成员

class Person {
    public name: string;
    public static age: number;

    constructor(name: string, age: number) {
    }
}

class Animal {
    public name: string;

    constructor(name: string, age: number) {
    }
}

let p: Person;
let a: Animal;

a = p;
p = a;

私有属性：

class Person {
    private name: string;
}

class Animal {
    private name: string;
}

let p: Person;
let a: Animal;

p = a;
a = p;

受保护属性：

class Person {
    protected name: string;
}

class Animal {
    protected name: string;
}

let p: Person;
let a: Animal;

p = a;
a = p;